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CYBERAMP 380, COPYRIGHT MARCH 2002, AXON INSTRUMENTS, INC.

March 2002

CyberAmp 380

OPERATOR'S MANUAL

Part Number 2500-117 Rev F, Printed in U.S.A.

No part of this manual may be reproduced, stored in a retrieval system, or transmitted, in any form or

by any means, electronic, mechanical, photocopying, microfilming, recording, or otherwise, without

written permission from Axon Instruments, Inc.

QUESTIONS? Telephone +1(510) 675-6200 or Fax +1(510) 675-6300

E-mail: tech@axon.com

Summary of content (157 pages)

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March 2002 CyberAmp 380 OPERATOR'S MANUAL Part Number 2500-117 Rev F, Printed in U.S.A. Copyright 1992, 1996, 2002 Axon Instruments, Inc. No part of this manual may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording, or otherwise, without written permission from Axon Instruments, Inc. QUESTIONS? Telephone +1(510) 675-6200 or Fax +1(510) 675-6300 E-mail: tech@axon.
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Declaration of Conformity Manufacturer: Axon Instruments, Inc.
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IMPORTANT INFORMATION WARNING IF THIS EQUIPMENT IS USED IN A MANNER NOT SPECIFIED BY THE MANUFACTURER, THE PROTECTION PROVIDED BY THE EQUIPMENT MAY BE IMPAIRED. Power-Supply Voltage Selection and Fuse Changing Mains Supply Requirements The CyberAmp 380 uses 30 Watts of power and can operate from either two Mains Supply voltages: 115 V~ or 230 V~. Variations in the voltage should not exceed ±10%. Frequency can range from 50 to 60 Hz.
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RENSEIGNMENTS IMPORTANTS ATTENTION L'EMPLOI DE CE MATERIEL D'UNE MANIERE DIFFERENTE A CELLE SPECIFIEE PAR LE FABRICANT AFFECTERA LE NIVEAU DE PROTECTION FOURNIT PAR L'APPAREIL. Sélection du voltage et changement du fusible Voltage d’Alimentation Le CyberAmp 380 utilise une puissance de 30 Watts et fonctionne á l’aide d’une alimentation principale pouvant correspondre á 115 V~ ou 130 V~. Les variations de voltage ne doivent pas excéder ±10%. La fréquence peut varier de 50 á 60 Hz.
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WICHTIGE INFORMATIONEN UNZULÄSSIGE VERWENDUNG DIESER APPARAT IST NICHT VORGESEHEN, BEI MENSCHLICHEN VERSUCHEN VERWENDET ZU WERDEN UND AUCH NICHT AN MENSCHEN IN IRGENDEINERWEISE ANWENDBAR. WARNUNG WEN DIESER APPARAT IN EINER ART UND WEISE ANGEWENDET WIRD, DIE NICHT VOM HERSTELLER SPEZIFISCH ERWÄHNT WIRD, KANN DIE SCHUTZVORRICHTUNG DES APPARATES BEEINTRÄCHTIGT WERDEN.
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INFORMACION IMPORTANTE ADVERTENCIA SI ESTE EQUIPO SE USA DE MANERA NO ESPECIFICADA POR EL FABRICANTE SE PODRÍA PERDER LA PROTECCIÓN PROVISTA POR EL EQUIPO. Selección del suministro de corriente y cambio de fusibles Suministro de energía requerido El CyberAmp 380 utiliza 30 vatios y puede funcionar con cualquiera de los dos suministros de voltaje: 115 V~ ó de 230 V~. Las variaciones en el voltaje no deben exceder ±10%. La frecuencia puede variar entre 50 y 60 Hz.
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Explanation of symbols Explication des symboles Erklärung der verwendeten symbole Explicación de símbolos Description Description Beschreibung Descripción Symbol Symbole Symbol Símbolo Direct current Courant continu Gleichstrom Corriente continua ~  o Alternating current Courant alternatif Wechselstrom Corriente alterna On (Supply) Allumé (alimentation) An (Netz) Encendido (suministro) Off (Supply) Éteint (alimentation) Aus (Netz) Apagado (suministro) On (Supply) Allumé (alimentation) An (Netz) Encendi
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SAFETY SÉCURITÉ The CyberAmp 380 and associated probes are not intended to be used and should not be used in human experimentation. Nor should they be applied to humans in any way UNLESS specially identified, isolated probes are used. Such probes are clearly identified by one of the symbols shown in Figure 1. Le CyberAmp 380 et ses sondes ne sont pas prévues pour être utilisées et ne doivent pas être utilisées pour l’expérimentation humaine.
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i COPYRIGHT The circuits and information in this manual are copyrighted and must not be reproduced in any form whatsoever without written permission from Axon Instruments, Inc. VERIFICATION This instrument is extensively tested and thoroughly calibrated before leaving the factory. Nevertheless, researchers should independently verify the basic accuracy of the instrument using suitable test signals. CYBERAMP 380, COPYRIGHT MARCH 2002, AXON INSTRUMENTS, INC.
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iii TABLE OF CONTENTS INTRODUCTION ...............................................................................................................................1 FUNCTIONAL DESCRIPTION .........................................................................................................5 Channel Features ........................................................................................................................5 General Features.............................................................
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iv iv AC Coupling and Autozeroing .................................................................................................. 26 Time Constant ...................................................................................................................... 28 Saturation.............................................................................................................................. 29 Offset Control ...................................................................................
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v Self Heating...........................................................................................................................50 Isolation.................................................................................................................................50 Insulation Techniques ...........................................................................................................50 AI 400 SERIES SmartProbes ........................................................................
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vi vi Wheatstone Bridge Strain Gauge Circuits............................................................................ 61 Linear Potentiometers........................................................................................................... 62 Rotary Potentiometers .......................................................................................................... 62 Panel Switch ............................................................................................................
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vii Menus .........................................................................................................................................90 PC Menus ..............................................................................................................................90 Macintosh..............................................................................................................................91 Suggestions for Improving Performance ...............................................
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INTRODUCTION Page 1 INTRODUCTION The CyberAmp 380 provides the front-end signal conditioning for a versatile computer-based data acquisition system. It is a comprehensive eight-channel instrument suitable for almost all forms of laboratory signal amplification, filtering, and transduction. The signal-conditioning functions performed by the CyberAmp 380 are gain amplification, AC and DC coupling, low-pass filtering, notch filtering, overload detection, offset removal, and DC level shifting.
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Page 2 INTRODUCTION Below is a partial list of transducers that can be accommodated to the CyberAmp either by AI 400 series SmartProbes or by user-supplied adapters. Current  AI 400 series picoammeter probes. Ion-selective electrodes  calcium, potassium, etc. Use AI 400 series amplifier probes. Low-impedance electrodes  direct connection to BNC inputs. Measuring instruments  direct connection to BNC inputs. pH  use AI 400 series low-noise amplifier probes.
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INTRODUCTION Page 3 In many recording situations, sound is helpful in determining the quality of the recording. Typical situations include EMG conduction velocity experiments and extracellular spike activity measurements. To this end, the CyberAmp 380 is furnished with a versatile audio monitor that samples the signal activity on any of its eight channels or an external input. Two audio modes are provided: Tone and Click. "Tone" is most suitable for listening to DC levels and slowly changing signals.
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FUNCTIONAL DESCRIPTION Page 5 FUNCTIONAL DESCRIPTION The CyberAmp 380 programmable transducer amplifier can amplify, filter, offset and AC couple signals on eight independent channels. There are no front-panel controls for the signal conditioning pathway because the instrument is intended as the front-end signal conditioner in a computer data acquisition system. The CyberAmp is controlled by a host computer communicating over a serial port.
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Page 6 FUNCTIONAL DESCRIPTION Figure 2. This figure shows the signal processing pathway. CYBERAMP 380, COPYRIGHT MARCH 2002, AXON INSTRUMENTS, INC.
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FUNCTIONAL DESCRIPTION 4) Page 7 Gain. The gain can be set at discrete values ranging from x1 to x20,000. If all amplification of a signal occurred before the low-pass filter, it is likely that noisy signals would drive the filter into saturation even though the signal itself might be within the linear range of the electronics. If, on the other hand, all amplification occurred after the filter, the inherent noise of the filter would be amplified. The CyberAmp 380 implements a flexible approach.
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Page 8 9) FUNCTIONAL DESCRIPTION Input connectors. There are two inputs for each channel: a BNC connector for single-ended inputs and a 15-pin D connector for single-ended or differential inputs. The inner contact on the BNC is connected to the positive input of the amplifier. The shell of the BNC is connected to ground.
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FUNCTIONAL DESCRIPTION 5) Page 9 connector. The outputs from all eight channels are available on a single 15-pin connector on the rear panel. LINK Typically this connector would be attached to a special cable to take the eight outputs directly to the A/D board of the computer, eliminating the need to take the signals via an intermediate BNC connector box.
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Page 10 FUNCTIONAL DESCRIPTION 10) RS-232 interface. The CyberAmp communicates with the host computer over a standard serial communications port, known as an RS-232 interface. All communications are initiated by the host. Communications on the serial port must operate at a speed between 300 bits per second (baud) and 19,200 baud. The CyberAmp 380 automatically adapts itself to operate at the rate initiated by the host computer.
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FUNCTIONAL CHECKOUT Page 11 FUNCTIONAL CHECKOUT A new CyberAmp 380 should be subjected to a functional checkout to ensure the proper functioning of the instrument. All units are burned-in and thoroughly tested at the factory before shipping. If any shipping damage or problems with the functional checkout are observed, please call the factory. For the initial checkout, the CyberAmp 380 should be situated on a benchtop away from other equipment. Do not install in a rack until the checkout is complete.
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Page 12 FUNCTIONAL CHECKOUT The computer will respond with the following status information: Program CMD300 Version 1.nnn Copyright (c) Axon Instruments Inc. 1990. All rights reserved. CyberAmp reset to factory defaults. CYBERAMP 380 (Serial number nnnn) (Microcode version 1.
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FUNCTIONAL CHECKOUT 9) Page 13 Issue the command: CMD300 FILTER OFF GAIN 1 to bypass the low-pass filter on all channels. Select channel 1 on the rotary dial in the audio monitor section on the front panel. Move the toggle switch to the TONE position. Rotate the VOLUME control to its midpoint. Rotate the SQUELCH/FREQUENCY control to about three quarters of maximum. The tone should rapidly change between two frequencies. Adjust the SQUELCH/FREQUENCY control to change the baseline frequency of the tone.
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TYPICAL CONFIGURATIONS Page 15 TYPICAL CONFIGURATIONS The CyberAmp 380 excels when combined with a computer, an analog-to-digital (A/D) converter, and a software program, such as AxoScope, that makes the computer a digital tape recorder. Such a system is functionally superior to laboratory tape recorders and chart recorders. The configuration of the CyberAmp and its sensors, including units of measure and gains for all channels, is known at all times and stored with the data.
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Page 16 TYPICAL CONFIGURATIONS Almost any A/D interface can be used. The Digidata 1322A and previous interfaces from Axon Instruments are suitable, as are interfaces from many other manufacturers. Almost any computer type is acceptable (with appropriate software), because nearly all computers support RS-232 serial communications. Null modem cables suffice for the communications link, but the RS232-01 cable from Axon Instruments is specifically designed for this task.
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TYPICAL CONFIGURATIONS Figure 5. Here no interface box is used. Instead, a special cable, supplied by the user, carries the eight analog outputs from the CyberAmp LINK connector directly to an A/D board plugged into the computer. Figure 6. A chart recorder has been added to the configuration shown in Figure 5. CYBERAMP 380, COPYRIGHT MARCH 2002, AXON INSTRUMENTS, INC.
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Page 18 TYPICAL CONFIGURATIONS Figure 7. In this configuration, the computer does not acquire data. Instead, a laptop computer controls the CyberAmp and the data is recorded on a chart recorder. CYBERAMP 380, COPYRIGHT MARCH 2002, AXON INSTRUMENTS, INC.
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GENERAL INFORMATION Page 19 REFERENCE SECTION — GENERAL INFORMATION Power Supply Voltage Selection and Fuse Changing Supply Voltage The CyberAmp 380 operates from all international supply voltages. The two input ranges are: 1) 115 V : For 100 Vac to 125 Vac operation. 2) 230 V : For 200 Vac to 250 Vac operation. Note: When shipped, the AC mains fuse and fuse holder are removed from the back of the CyberAmp 380 and placed in a bag stapled to the handle.
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Page 20 GENERAL INFORMATION Grounding and Hum Grounding The analog ground inside the CyberAmp 380 is tied to the computer ground via a 10 Ω resistor. The analog ground is defined as that ground connected to the shields of the BNC connectors and to pin 10 of the multipin input connector. The computer ground comes from the computer and is carried by the RS-232 serial communications cable.
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GENERAL INFORMATION 8) Page 21 Experiment. While hum can be explained in theory (e.g. direct pickup or ground loops), the practical reduction of hum is an empirical matter. Following the rules above is the best start. The final hum level can often be kept to less than 1 µVp-p, input referred. One technique that should not be used to reduce hum is the delicate placement of cables so that a number of competing hum sources cancel out. Such a set up is too prone to accidental alteration.
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Page 22 GENERAL INFORMATION Expansion To increase the number of signal conditioning channels, if your software supports it, up to ten CyberAmp 380s may be "daisy chained" to one computer serial port. The RS-232 OUT port of the first CyberAmp is connected to the RS-232 IN port of the next CyberAmp, and so on. The interconnection cable should be a simple 25-pin flat cable, such as the RS232-02 cable from Axon Instruments.
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PRINCIPLES OF OPERATION Page 23 REFERENCE SECTION -- PRINCIPLES OF OPERATION Low-Pass Filter Filter Type The low-pass filters in the CyberAmp 380 are fourth-order Bessel filters. The Bessel filter is sometimes called a linear-phase or constant delay filter. All filters alter the phase of the sinusoidal components of the signal. In a Bessel filter, the change in phase with respect to frequency is linear. Put differently, the amount of signal delay is constant in the pass band.
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Page 24 PRINCIPLES OF OPERATION Amplitude Characteristics For signals at the selected -3dB frequency the amplitude response of the low-pass filter is attenuated by 3 dB. This means that the amplitude of the signal at the output of the filter is 1/√2 (i.e., 0.7071) of the amplitude of the input signal. Equivalently, the -3 dB frequency is the frequency at which the signal power at the output of the filter has fallen to half of the power of the input signal.
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PRINCIPLES OF OPERATION Page 25 Typically, as the order of a filter increases, the attenuation in the pass band decreases, and the slope of the voltage attenuation in the pass band becomes flatter. For most data, there is little to be gained by increasing the order of a Bessel filter above four. If the input noise spectrum is constant with frequency (i.e., white), a fourth-order Bessel filter reduces the noise in the stop band almost as much as an eighth-order filter.
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Page 26 PRINCIPLES OF OPERATION Pre-Filter vs. Post-Filter Gain When low-level signals are recorded, it is essential that the first-stage amplification be sufficiently high to minimize the noise contributed by succeeding stages. For example, in a microphone amplifier the tiny output from the microphone is first coupled into an extremely low-noise transistor amplifier.
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PRINCIPLES OF OPERATION Page 27 INPUT 10 Hz 1 Hz 0.1 Hz 500 ms Figure 10. A 1 Hz square wave is AC coupled at three different frequencies. The distortion is progressively reduced as the AC coupling frequency is reduced from 10 Hz to 0.1 Hz. In all cases the DC content of the signal is removed. The problem with using the lowest AC coupling frequencies is that slow shifts in the baseline may not be rejected. Furthermore, transient shifts in the baseline might take a long time to recover.
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Page 28 PRINCIPLES OF OPERATION DC 10 Hz 1 Hz 0.1 Hz DC WITH AUTOZERO AUTOZERO Figure 11. The top trace shows an ECG signal that is sitting on a 5 mV offset resulting from electrode junction potentials. The pulses are distorted at AC coupling frequencies from 10 Hz down to 0.1 Hz. In the bottom trace, a zero command is issued to the CyberAmp at the time indicated by the arrow. The DC component is immediately removed, but the pulses are unaffected.
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PRINCIPLES OF OPERATION Page 29 Saturation The AC coupling circuit is the first circuit in the CyberAmp. If a large step is applied to AC-coupled inputs, the AC coupling capacitors reject the step voltage with a time constant determined by the AC coupling frequency. If the CyberAmp amplifiers are set to high gain, the output might be saturated for a considerable time.
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Page 30 PRINCIPLES OF OPERATION Pre-filter Gain x1 x10 x100 Input-referred Range ±3.00 V ±300 mV ±30.0 mV Input-referred Resolution 100 µV 10 µV 1 µV Rather than adding it to the input, the DC offset is added after the pre-filter amplifier for two reasons. First, it is technically difficult to add an offset at the input without compromising either the noise, the common-mode rejection ratio, or the input impedance.
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PRINCIPLES OF OPERATION Page 31 A B Figure 12. Part A shows an inappropriate use of the notch filter. The notch filter is tuned for 50 Hz. The input to the notch filter is a 10 ms wide pulse. This pulse has a strong harmonic at 50 Hertz that is almost eliminated by the notch filter. Thus the output is grossly distorted. B shows an appropriate use of the notch filter. An ECG signal is corrupted by a large 60 Hz component that is completely eliminated by the notch filter.
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Page 32 PRINCIPLES OF OPERATION Audio Monitor When monitoring data, experimenters need not be limited to their sense of sight. The data may also be monitored with great sensitivity by ear. The data are input to an audio monitor and fed to a loudspeaker or to a set of headphones. The audio monitor input is chosen from the output of any of the eight signal-processing channels or from an external input connected to a BNC on the rear panel.
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PRINCIPLES OF OPERATION Page 33 SQUELCH THRESHOLD OV SQUELCH THRESHOLD Figure 13. The audio monitor is active during the time indicated by the thick horizontal bar because the absolute value of the signal exceeds one of the squelch thresholds (dashed lines). At all other times the signal level is within the squelch thresholds and the audio circuit is disabled. In TONE mode, the OFFSET control (physically the same control as SQUELCH) alters the base frequency of the tone.
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Page 34 PRINCIPLES OF OPERATION Electrode Test The electrode resistance is measured for several reasons. First, it establishes the basic continuity of the electrode circuit. Sometimes electrodes or electrode leads break, causing the measured resistance of previously low resistance electrodes to go very high and consequently resulting in no incoming data. Second, it verifies that the electrode is making acceptable contact, as in surface electrodes.
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PRINCIPLES OF OPERATION Page 35 Figure 15. Change in the waveform of an Electrode Test response produced by lowpass filtering. Two Ag/AgCl wires were immersed in saline and directly connected to the differential inputs of the CyberAmp. The upper trace shows the Electrode Test response recorded with the lowpass filter set to 10 kHz. The lower trace shows the same response recorded with the lowpass filter set to 12 Hz.
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Page 36 PRINCIPLES OF OPERATION Box 1 1) From Equation 2; R e = 1 MΩ V0 Gain − V0 2) For low values of Re, the 1 Vp-p square wave drives an approximately 1 µAp-p current into the electrode. Thus the electrode resistance can be approximately determined from: R e = 1 MΩ V0 Gain R e < 50 kΩ Giving Re = 1 kΩ for each mV at Vin. Figure 16. These graphs can be used to determine the electrode resistance measured during Electrode Test. The solid line in Graph A represents equation 1 in the text.
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PRINCIPLES OF OPERATION Page 37 Input Coupling To properly measure the electrode impedance, one input on each channel should be grounded while the other input is DC coupled. This is very important. If the electrodes on both inputs of a channel have the same resistance and neither input is grounded during the Electrode Test measurement, then the measurement will indicate that the total resistance is 0 kΩ.
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Page 38 PRINCIPLES OF OPERATION Active Probes Active SmartProbes have headstages in which signal amplification occurs before the signal is fed to the CyberAmp. Support for the Electrode Test facility is generally not as straightforward as in passive probes. There are two basic reasons for this. First, it is undesirable for most active probes to have 1 MΩ resistors connected to their inputs; this would decrease the input resistance and perhaps degrade the noise performance.
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PRINCIPLES OF OPERATION Page 39 resistor. Knowing the measured current (I), the resistance can be simply calculated from Ohm's law, viz.: Re (GΩ) = 1 Vp-p / I (nAp-p) Common-Mode Rejection Ratio In general, the information that the researcher wants to record is the difference between two signals connected to the positive and negative inputs of a differential amplifier. The two signals often contain a common component that does not contain relevant information.
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Page 40 PRINCIPLES OF OPERATION The input resistance of the CyberAmp 380 main unit is 1 MΩ. In general, electrodes can be directly connected to the CyberAmp either if the difference between the resistance of the positive and negative electrodes is a few kΩ or less or if there is no common-mode signal. If there is a large common-mode signal and a source imbalance of more than a few kΩ, a high input resistance amplifier probe should be used.
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PRINCIPLES OF OPERATION Page 41 Troubleshooting 1) General It has been our experience at Axon Instruments that the majority of troubles reported to us have been caused by faulty equipment connected to our instruments. If a problem is encountered please disconnect all instruments and probes from the CyberAmp 380. Ideally, remove the CyberAmp from the rack. Work completely through the Functional Checkout that commences on page 11. This can often uncover a problem in the set up of the CyberAmp.
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TRANSDUCERS Page 43 TRANSDUCERS Many different types of transducers are used in science and engineering. They have various requirements for excitation voltages, amplification, recording techniques, and mechanical connections. In the past this variety has required a different amplifier for each transducer type. The CyberAmp 380 introduces a convenient new approach to interfacing transducers.
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Page 44 TRANSDUCERS thermistor types. These can be custom interfaced to the CyberAmp 380 by using the AI 490 Connector and AI 491 Cable kits. 2) Temperature transducers that produce an output current proportional to absolute temperature. The most notable temperature-dependent current sources are the Analog Devices AD590, with a temperature range of -55 to +150°C, and the lower-cost AD592, with a temperature range of -25 to +105°C.
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TRANSDUCERS Page 45 available thermocouples have diameters as small as 25 µm and thermal time constants as short as 2 ms (High Temperature Instruments Corp., Omega Engineering). Table 1. ANSI Type E J K R S T Common Thermocouples Min Value (°C) Max Value (°C) -200 -200 -200 0 0 -200 900 750 1250 1450 1450 350 Sensitivity at 20°C (µV/°C) 60.48 51.45 40.28 5.80 5.88 40.
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Page 46 TRANSDUCERS EMG, EEG, ECG Recording 1) EMG An electromyogram (EMG) can be recorded in many ways, each with its own special requirements. Surface EMG electrodes have the advantage of being non-invasive but suffer from artifacts or even total loss of signal during movements. They are also not as selective as implanted EMG electrodes. Implanted electrodes must be capable of remaining in the same location and must be of an appropriate size and separation.
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TRANSDUCERS Page 47 Nerve Cuffs Nerve cuff recordings have a frequency response up to 10 kHz and an amplitude in the low µV range. The AI 402, x50 Ultra Low Noise Differential amplifier probe is designed for this application, with 10 kHz noise of less than 0.18 µVrms (1.1 µVp-p) in the 0.1-10 kHz bandwidth. The nerve cuffs themselves are simply made by running fine bared stainless steel wires through a small length of silicone tubing that is split longitudinally.
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Page 48 TRANSDUCERS capacitively couple into the EMG leads. This problem can be eliminated by differentially recording from a twisted pair of leads, or by a different placement of EMG leads. 3) The high-frequency components of the signal are filtered out. The source resistance and the capacitance of the cable to the amplifier act as a simple RC low-pass filter. Electrical cables can provide 30-100 pF capacitance per foot (100-300 pF/meter).
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TRANSDUCERS Page 49 Pressure High quality pressure transducers have historically been very expensive and suffered from a significant temperature sensitivity. A variety of semiconductor pressure transducers having improved temperature sensitivity are now available at low cost. When measuring very low pressures the height of the pressure transducer should be the same as the sense location, avoiding hydrostatic errors introduced by fluid filled catheters.
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Page 50 TRANSDUCERS Self Heating When an excitation current or voltage is applied across a temperature measurement sensor, power is dissipated as heat, causing the temperature of the sensor to rise above the ambient temperature to be measured. This is referred to as "self heating". For most of the temperature sensors used in physiology, it is necessary to keep the power dissipation to less than a few milliwatts. If this condition is met, temperature changes of less than 0.01°C can be measured.
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AI 400 SERIES PROBES Page 51 AI 400 SERIES SmartProbes This section describes the current SmartProbes. The reader should consult the most recent Axon Instruments price list to determine what probes are available. Axon Instruments also provides users with application circuits and details about transducer characteristics and use. Axon welcomes any interesting application that has not been discussed in this manual.
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Page 52 AI 400 SERIES PROBES AI 401, x10, Low-Noise Differential Amplifier This amplifier provides low noise, high input impedance, a good common-mode rejection ratio, and low drift. The rms noise of 0.7 µV in the DC-10 kHz bandwidth is equivalent to the thermal noise of a 5 kΩ resistor.
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AI 400 SERIES PROBES Page 53 The AI 403 picoammeter probe is applicable to a broad range of physiological and other measurement tasks, such as: Scanning tunneling microscope (STM) Surface corrosion studies Photomultiplier tube (PMT) amplifier Infrared (IR) detector amplifier Photodiode amplifier Dielectric breakdown studies Secondary electrode emission Current transients in switches Automatic IC test equipment The 10 GΩ feedback resistor is suitable for the measurement of current ranging from a few femtoa
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Page 54 AI 400 SERIES PROBES Kits AI 490 Connector Kit The AI 490 connector kit helps researchers adapt amplifiers or transducers to the CyberAmp. The kit consists of a 15-pin D connector, a circuit board and a connector hood. The circuit board has a memory chip to provide the standard memory requirements expected of AI 400 series probes. Pads on the board enable the user to add a small number of components and to connect wires to the power supplies and inputs.
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AI 400 SERIES PROBES Page 55 When a SmartProbe is added to the system, it is common to re-start the data acquisition program to force the program to re-read the probe memory. Recommended Input Coupling The instruction sheets for the individual AI 400 series probes contain recommendations concerning the CyberAmp input configuration that should be used.
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Page 56 MAKING YOUR OWN ADAPTER OR ACTIVE PROBE MAKING YOUR OWN ADAPTER OR ACTIVE PROBE One can easily make custom transducer adapters or active probes for the CyberAmp. For each channel, the 15-pin D connector provides a ±15 V power supply, a +5.000 V precision excitation voltage, and positive and negative inputs that will directly accept most signals. In its simplest form, the custom adapter can use a plain 15-pin male D connector, available from any electronic components vendor.
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MAKING YOUR OWN ADAPTER OR ACTIVE PROBE Page 57 EEPROM A 256-byte serial EEPROM (i.e., non-volatile memory chip) is located on a small circuit board within the D connector of each probe. The first 128 bytes in the probe EEPROM contain reserved information records. They are generally not changed except to recalibrate. The remaining 128 bytes are undefined.
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Page 58 MAKING YOUR OWN ADAPTER OR ACTIVE PROBE Series 700 Thermilinear Circuit 5.000 V (4) R1 3K13 0.1% 1.87 V U1 R4 3K20 0.1% R5 6R25 0.1% R2 250 0.1% R3 1K6 0.1% U2 T1 1.62 V INPUT (1) INPUT (2) T2 ANALOG GROUND ( 10 ) Figure 20. Circuit for Yellow Springs Instrument Co. (YSI) series 700 temperature measurement probes. Probes plug into a phone jack. T1 and T2 are the two thermistor connections inside the probe. The 1.
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MAKING YOUR OWN ADAPTER OR ACTIVE PROBE Page 59 software analysis. AD590 Integrated Circuit Temperature Sensor 5.000 V ( 4 ) AD59 10 mV/°K R3 10K INPUT ( 1 ) INPUT ( 2 ) R1 2K ( GAIN ) R2 9K ANALOG GROUND ( 10 ) Figure 22. The Analog Devices AD590 temperature measurement integrated circuit allows 1 µA/°K to flow in the circuit. R1 is trimmed so that the circuit sensitivity is exactly 10 mV/°K. R3 is used to zero the nominal 2.73 V response at 0°C.
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Page 60 MAKING YOUR OWN ADAPTER OR ACTIVE PROBE Type J and Type K Thermocouples 15 V ( 15 ) CONSTANT OR ALUMEL 14 13 11 9 8 INPUT ( 1 ) AD594 OR AD595 1 4 7 IRON OR CHROME 15 V ( 8 ) ANALOG GROUND ( 10 ) Figure 24. Thermocouple interface. The AD594 (for type J thermocouples) and the AD595 (type K) integrated circuits from Analog Devices allow for an extremely simple thermocouple interface. The output is 10 mV/°C. Cold junction compensation is built in.
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MAKING YOUR OWN ADAPTER OR ACTIVE PROBE Page 61 Current Probes Photodiode Amplifier R1 100 MΩ CURRENT INPUT 15 V ( 15 ) U 100 mV/nA 1 INPUT ( 2 ) 15 V ( 8 ) C1 0.1 C2 0.1 ANALOG GROUND ( 10 ) Figure 26. Current-to-voltage converter. The output voltage of U1 is proportional to -R1 times the input current (I). Since this inverse output is connected to the negative input of the CyberAmp, the output of the CyberAmp will be positive for positive values of I.
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Page 62 MAKING YOUR OWN ADAPTER OR ACTIVE PROBE 5.000 V ( 4 ) LM334 16.1 Ω SPX SENSOR 909 Ω INPUT ( 1 ) ANALOG GROUND ( 10 ) INPUT ( 2 ) Figure 28. Temperature compensated pressure sensor. In this circuit, type SPX pressure sensors from SenSym Corporation are temperature compensated using the type LM334 temperature-dependent current source from National Semiconductor Corp. The LM334 output current rises linearly with temperature at +0.336%/°C.
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MAKING YOUR OWN ADAPTER OR ACTIVE PROBE Page 63 Panel Switch Foot Switch R1 100Ω 5.000 V ( 4 ) INPUT ( 1 ) C2 0.1µ C1 1µ ANALOG GROUND ( 10 ) Figure 30. Switch interface. This circuit can be used to interface a change-over switch to the CyberAmp. Such switches would typically be used to activate one of the digital inputs or a counter input in the data acquisition system. Capacitor C2 eliminates false triggering due to contact bounce. Resistor R1 limits the transient current drawn from the 5.
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CMD300 CONTROL SOFTWARE Page 65 CMD300 CONTROL SOFTWARE For PCs, the CyberAmp 380 is supplied with a DOS command-line program called CMD300 (for Command 300) that can be used to control all of the functions and capabilities of the instrument. The program can be used in command-line mode, or it can accept commands interactively or from a command file on disk. Installation The CMD300 program and the other software supplied on the CD can be installed on a hard disk in a directory called \CMD300.
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Page 66 CMD300 CONTROL SOFTWARE respecified unless the group is changed. The syntax of channel selection is flexible and allows lists and ranges.
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CMD300 CONTROL SOFTWARE CMD300 STATUS Page 67 DEFAULTS Produces: Program CMD300 Version 1.0 Copyright (c) Axon Instruments Inc. 1990. All rights reserved. CyberAmp communication on COM 2 at 19200 baud. Channels 1-8 selected by default. Responses are verbose. Most PC computers should be able to communicate with the CyberAmp at 9600 or 19,200 bps.
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Page 68 CMD300 CONTROL SOFTWARE Entering an alphanumeric key as the first character of the command line will erase the previous command line. Again, an will restore the previous command line. Hit to have the program process the command line. The output area of the screen displays the last few commands that were entered and the program's response to each command.
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CMD300 CONTROL SOFTWARE Page 69 Command Reference Summary of Commands The CyberAmp commands are divided into two groups: Basic Commands which are frequently used, and Advanced Commands, used infrequently or used to test the unit.
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Page 70 CMD300 CONTROL SOFTWARE Command Details of Basic Commands The following basic commands and modifiers are supported by the CMD300 program. The minimum abbreviation of each command and modifier is indicated by large capitalized text. 1) BAUD or BAUD DEFAULT This command specifies the speed of communication with the CyberAmp. The default speed of 9600 bps is assumed by CMD300 when first run. The last speed is retained between executions of the program.
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CMD300 CONTROL SOFTWARE 4) COUPLING or COUPLING or COUPLING Page 71 + - + - This command sets the positive and/or negative input coupling for the selected channels. The allowed values for are: GND, DC, 0.1, 1, 10, 30, 100 and 300. 5) DEVICE or DEVICE OFF This command specifies Axon expandable RS232 bus device numbers.
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Page 72 7) CMD300 CONTROL SOFTWARE FINDSPEED This command determines the optimal speed for communicating with the CyberAmp. Starting with 19200 bps, the program attempts to communicate with the CyberAmp and reduces its speed until it finds a speed that is reliable and error-free. If FINDspeed selects a speed different than the current speed, then the user is prompted to confirm that the selected speed will be the default in future executions of the program.
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CMD300 CONTROL SOFTWARE 12) OFFSET Page 73 The OFFSET command specifies the DC offset adjustment that is added after the pre-filter gain amplifier. The is specified in millivolts and can be in the range -3000.0 to +3000.0 mV. Because this offset is introduced after the pre-filter gain amplifier, the inputreferred offset value depends on the gain setting of the pre-filter amplifier.
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Page 74 CMD300 CONTROL SOFTWARE The information indicates that for channel number 1 there is an AI 410 SmartProbe attached to the CyberAmp input connector, its positive input is DC-coupled and its negative input is grounded. The overall gain is 20 and is composed of a pre-filter gain of 10 and an output gain of 2. The low-pass filter 3 dB cutoff is set at 10 kHz and the notch filter is bypassed. A +50 mV, input-referred DC offset is added to the input signal after the filter.
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CMD300 CONTROL SOFTWARE Page 75 Command Details of Advanced Commands The following advanced commands and modifiers are support by the CMD300 program. The minimum abbreviation of the commands and modifiers is indicated by the large capitalized text portion of each token. 21) BEEP This command causes the computer to briefly beep. It is useful in the command-file mode to signal the user. 22) CONTINUOUS This command sets the program into continuous command-file mode.
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Page 76 27) CMD300 CONTROL SOFTWARE RAW The RAW command allows the user to pass an arbitrary command to the CyberAmp. The remainder of the command line is passed unedited to the CyberAmp. CMD300 will add the leading "AT" command prefix and device number if applicable. Any text response from the CyberAmp is displayed. 28) READPROBE This command reads and displays information stored in the EEPROM of any SmartProbe attached to the CyberAmp.
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CMD300 CONTROL SOFTWARE 33) Page 77 STEP This command sets the program into step-by-step command-file mode. This command could be used both on the command line and in a command file to switch the command file processing into step-by-step mode. In the example below, if the following command file EXAMP.CMD is being processed continuously, then it will switch to step mode at line 3.
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Page 78 36) CMD300 CONTROL SOFTWARE WRITEPROBE This command allows the user to change or update the standard information that is stored in the EEPROM of a probe attached to a channel of the CyberAmp. The is any allowed channel number for the CyberAmp.
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QUICK300 CONTROL SOFTWARE Page 79 QUICK300 CONTROL SOFTWARE The Quick300 spreadsheet program controls the CyberAmp from PC computers that have a DOS operating system. It presents a spreadsheet that simultaneously shows the values of the most needed CyberAmp functions. Each cell in the spreadsheet shows the current setting of a function on one channel. A function is changed by entering a new value in its cell, or by scrolling through the permissible values.
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Page 80 QUICK300 CONTROL SOFTWARE port speed should be set to fast unless a communications problem is experienced. To accept the changes in this or any dialog form, exit the form with the keystroke . To reject the changes, exit the form with . The COM port number and the communication speed are saved in the file QUICK300.INI. The first time that QUICK300 is run, it will set the CyberAmp to its factory default settings.
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QUICK300 CONTROL SOFTWARE Page 81 Positive input, Negative input. The positive and negative inputs of the CyberAmp can be set either to DC, GND, or AC, for direct coupling, grounding, or AC coupling, respectively. If set to AC coupling, the high-pass AC filter setting is taken from the following row, AC cutoff (Hz). Copy rows and columns. With the Copy rows command, copy the value in the current cell to all other cells in its row. This is used to set a function on all channels to the same value.
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Page 82 QUICK300 CONTROL SOFTWARE Command Line Options A number of options can be set at the time that QUICK300 is loaded into memory and run. These options allow the user to automatically load a settings file, to accept the present values of the CyberAmp unchanged, to load a settings file and return to DOS, or to explicitly set the video adapter mode. The options can be displayed by running QUICK300 with the help option.
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CyberControl SOFTWARE Page 83 CyberControl SOFTWARE CyberControl allows the user with a PC (running Windows 3.1 or higher) or Macintosh computer to completely control the CyberAmp. PC Installation From Windows, 1) Insert the CD. 2) Go to the \Windows\CyberControl folder on the CD and run the Setup.exe file. 3) An entry for CyberControl will be added to the Axon Laboratory folder in the Programs startup list.
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Page 84 CyberControl SOFTWARE Starting CyberControl When CyberControl is opened, the application automatically starts communications through the serial port. This is the Initialization portion of the startup sequence. If the CyberAmp is not powered up, or is not attached to the correct port, the application will ask if it should enter a demonstration mode, a feature designed to show the operation of the application when a CyberAmp is not attached.
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CyberControl SOFTWARE Page 85 the entire spreadsheet. With all of the cell selected, you can copy the value of all of the items in the entire spreadsheet. 2) PROBE COLUMN PC: The Probe field displays the identity of the attached probe. Click on the Probe Info button to bring up a Probe info window showing setup and calibration information for the probe. Macintosh: The Probe column lists the identity of each probe attached to the CyberAmp amplifier.
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Page 86 5) CyberControl SOFTWARE PRE-FILTER AMPLIFICATION COLUMN PC: The Initial Gain field displays the pre-filter amplification of the input signal. A few orders of magnitude are allowed. The setting can be typed in, or the spinner buttons can be used to scroll through the values. Any changes made are immediately applied to the CyberAmp channel, and the Total Gain field is also updated. Macintosh: The PreAmp column displays the pre-filter amplification valuesof the input signals.
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CyberControl SOFTWARE 9) Page 87 OUTPUT AMPLIFICATION PC: The Total Gain field displays the combination of the Initial Gain (pre-filter) along with any post-filter amplification. A predefined list of values are allowed. The setting can be typed in, or the spinner buttons can be used to scroll through the values. Macintosh: The OutAmp column displays the amount of post-filter amplification. Selecting a field pops up a list of available output gain settings.
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Page 88 CyberControl SOFTWARE Zeroing Channels PC: The CyberAmp series of signal conditioners have a hardware autozero function. To use this, select the channel to be zeroed, then use the Auto Zero button. The new value for the DC Offset will be displayed. Macintosh: Select the channel or channels to be zeroed by clicking in the Channel Number column to select the entire line. Then use the Zero Channel… option under the Cyber menu. The new value for the Offset will be displayed.
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CyberControl SOFTWARE Page 89 SmartProbe probe is disconnected or changed, these changes will be reflected in the window in real time. Figure 33. A Probe Info window with SmartProbe information. Communications Settings PC: The File / Configure Port command is used to modify the serial port settings used to communicate between the computer and the CyberAmp amplifier. 1) COM 1 - 4 can be selected, as well as running in a Demo mode. 2) The Configure button is used to change the Communications Rate.
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Page 90 CyberControl SOFTWARE 3) The Status Scanning Rate section controls the number of times per second that the overload status of the CyberAmp amplifier is polled. In addition, every ten cycles, the CyberControl program will determine the entire status of the CyberAmp amplifier, including the identity of the SmartProbe probes. This is a time-consuming operation, and for slower computers, this rate should be decreased to leave more time for other applications.
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CyberControl SOFTWARE Page 91 Save Settings… saves the current settings of the selected CyberAmp amplifier. If a file is already open, the current changes will be saved to this filename. Filenames cannot be longer than 8 characters in length, not including the extension. The CyberControl settings file extension (.CYB) needs to be appended to the filename, or the file will not be listed in the Load Settings display of filenames.
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Page 92 CyberControl SOFTWARE The File Menu The file menu is used for opening and saving data-sets, printing, and iconinzing windows. Open Settings… is used to recall any CyberAmp settings files that were previously saved. Close… closes the top-most window. Save Settings… saves the current settings of the selected CyberAmp amplifier. to the file already open. Save Settings As… saves the current settings of the selected CyberAmp amplifier to a file of any name.
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CyberControl SOFTWARE Page 93 The Cyber Menu The Cyber menu provides access to the special control functions of a CyberAmp signal conditioner. Zero Channel… zeros the selected channels. It invokes the autozero function of the CyberAmp amplifier, which zeroes the current input signal to the sampled value. Test Electrode… starts the Electrode Test on all channels of the CyberAmp amplifier. For more information see Using the Oscillator Test. Tune Notch Filter… turns on the notch filter tuning mode.
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Page 94 PROGRAMMER'S GUIDE PROGRAMMER'S GUIDE This chapter provides information for programmers who wish to add CyberAmp control to any program. This guide assumes that the programmer is familiar with the features and basic operation of the CyberAmp380, as described in the Introduction and Functional Description chapters. Serial-Port Communcations Communications with the CyberAmp 380 are via the RS-232 serial port. All commands and responses are in plain ASCII.
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PROGRAMMER'S GUIDE Page 95 "AT" Command Protocols The "AT" command set consists of ASCII commands and rules governing the commands that are sent by the host computer to instruments on the Axon expandable RS-232 bus. 1) Each command from the host must commence with the letters "AT". Upper case is required for the letters "AT" but case is irrelevant for subsequent characters in the command string.
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Page 96 PROGRAMMER'S GUIDE Libraries and Example Code The contents of the CD distributed with the CyberAmp 380 includes: 1) The DOS command-line control program CMD300.EXE. 2) The spreadsheet control program Quick300.EXE. 3) All of the source and information files necessary to compile CMD300.EXE and Quick300.EXE. 4) Communications libraries written in both QuickBASIC and C. These source files and libraries are not copyrighted.
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PROGRAMMER'S GUIDE Page 97 CyberAmp 380 Command Set  Details In the descriptions that follow, it is assumed that the character is sent at the end of the line, and for clarity, it will not be included in the command string. In all command strings, spaces and leading zeros are ignored.
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Page 98 PROGRAMMER'S GUIDE "D"  DC offset in microvolts Format ATdDnpvvvvvvv where d n p vvvvvvv = = = = device # (0-9) channel number (1-8) or "?" polarity of offset, positive (+) or negative (-) input referred offset in microvolts (7 digits) Examples AT1D2+1234500 AT1D2+1 234 500 AT2D7-0012345 AT2D7-12345 Set device 1, channel #2, to +1.234500 volts Set device 1, channel #2, to +1.234500 volts Set device 2, channel #7, to -0.012345 volts Set device 2, channel #7, to -0.
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PROGRAMMER'S GUIDE Page 99 "E"  EEPROM read/write/verify/serial# Format ATdERAn ssss llll ATdERHn ssss llll ATdEWAn ssss TEXT ATdEWHn ssss BYTES ATdEVn Read llll ASCII characters commencing from location ssss Read llll bytes in ASCII Hex from ssss Write TEXT starting from address ssss (0000=first byte) Write BYTES in hex, starting from address ssss.
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Page 100 PROGRAMMER'S GUIDE "F"  Frequency of low-pass filter Format ATdFnfffff Set low-pass filter cutoff frequency to ffff Hertz where d n fffff = device # (0-9) = channel number (1-8) or "?" = filter frequency in Hertz Examples Set device 3, channel #5, low-pass frequency to 24 kHz Set device 6, channel #5, low-pass frequency to 2 Hz Returns all possible values of filters in device 4 Response: 2 4 6 8 10 ...
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PROGRAMMER'S GUIDE "G"  Gain Format ATdGnxggg where d n x ggg = = = = device # (0-9) channel number (1-8) P or O (specifying Pre-filter amplifier or Output amplifier) pre-filter or output amplifier gain or "?" Examples AT1G2P1G2O200 AT1G2P100 AT1G2O005 AT4GP? AT3GO? Set device 1, channel #2, pre-filter gain = 1, output gain = 200 Pre-filter gain = 100, output gain unchanged Pre-filter gain unchanged, output gain = 5 Returns all possible values of pre-filter amplifier gain Response: 1 10 100 Returns a
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Page 102 PROGRAMMER'S GUIDE "L" - Load factory defaults Format ATdL where d = device # (0-9) Notes All channels are simultaneously set to the factory defaults.
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PROGRAMMER'S GUIDE Page 103 "O"  Overload report and reset Format ATdO where d = device # (0-9) Example AT3O Check overloads on all channels Channels 1, 3, 5 and 8 have overloaded since the last inquiry Response: 1 3 5 8 Notes Overloads are reported simultaneously for all channels that have overloaded since the last overload report. The list of channels that have overloaded contains the channel numbers separated by one or more spaces.
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Page 104 PROGRAMMER'S GUIDE "S"  Status report Format ATdSn where d n = = = = device # (0-9) channel number (1-8), to return channel status 0 or not present, to return device type, internal software version and serial number "+", to return complete status of all channels Examples Return status of device 5, channel #3 AT5S3 Response: 3 X=AI334 +=DC -=030 P=010 O=002 N=1 D=-0123450 F=40 Return device type, internal software version and serial number AT5S0 Response: CYBERAMP 380 REV 1.0.
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PROGRAMMER'S GUIDE Page 105 "T"  Test oscillators Format ATdTO+ ATdTOATdTN+ ATdTN- Turn on 10 Hz electrode-test oscillator Turn off 10 Hz electrode-test oscillator Turn on notch-filter test Turn off notch-filter test where d = device # (0-9) Notes During the notch-filter test, all of the CyberAmp channels are set to unity gain, zero offset, a low-pass filter frequency of 40 Hz, and the notch filter on. The settings prior to the test are saved and restored when the notch-filter test is turned off.
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Page 106 PROGRAMMER'S GUIDE "W"  Write settings to main memory Format ATdW Writes current settings to the CyberAmp main memory (EEPROM) where d = device # (0-9) Notes The internal memory is non-volatile; its contents are retained when the power is removed. The CyberAmp internal memory is not automatically updated after each command. The host program must specifically request a memory update by issuing the ATdW command.
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PROGRAMMER'S GUIDE Page 107 The following description of the library interface uses a non-language-specific calling convention that describes the calling interface to the support routines. All procedure arguments are passed by value in C (unless otherwise noted) and by reference in BASIC.
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Page 108 PROGRAMMER'S GUIDE 2) integer SetDeviceNumber (integer DevNum) This procedure enables the use of device numbers when communicating with the CyberAmp. This is only required if more than one device is using the same Axon expandable RS232 bus. Valid device numbers are in the range 0 to 9. To disable the use of device numbers once they have been enabled, call this procedure with the argument DEVICENULL. Device number usage is disabled by default.
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PROGRAMMER'S GUIDE Page 109 9) integer SetFilter (integer Channel, integer FilterVal) This routine is used to set the filter of the specified channel. Valid filter values are: 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 40 60 80 100 120 140 160 180 200 220 240 260 280 300 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 3000 4000 6000 8000 10000 12000 14000 16000 18000 20000 22000 24000 26000 28000 30000 To disable the filter, use the value FILTERDISABLED for the filter value.
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Page 110 PROGRAMMER'S GUIDE 15) integer GetChannelStatus (integer Channel, ref string StatusText) This procedure returns the status information about the specified channel. The status information includes the gain and filter settings, any attached probe type, notch filter setting, offset, couplings, etc. The format of the status information is the same as returned by the CyberAmp.
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PROGRAMMER'S GUIDE Page 111 Example Programs The following BASIC example programs illustrate the use of the CyberAmp support library to control the CyberAmp. The first program causes the CyberAmp to reload the factory defaults for the channel setup. 'The following INCLUDE statement is required to allow access to the 'routines that are exported by the C300LIB module. '$include: 'C300LIBB.INC' 'Initialize the CyberAmp interface module. if C300.Initialize% then end if 'Set the CyberAmp device number.
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Page 112 PROGRAMMER'S GUIDE The second example program displays the uninterpreted status text returned by the CyberAmp for the main unit and all channels. 'The following INCLUDE statement is required to allow access to the 'routines that are exported by the C300LIB module. '$include: 'C300LIBB.INC' 'Initialize the CyberAmp interface module. if C300.Initialize% then end if 'Set the CyberAmp device number. 'This step is not required if the device number is set to 'C300.DEVICENULL since this is the default.
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PROGRAMMER'S GUIDE Page 113 The following example program sets the gain of channel 1 of the CyberAmp to a value of 50. 'The following INCLUDE statement is required to allow access to the routines that are exported by the C300LIB module. '$include: 'C300LIBB.INC' 'Initialize the CyberAmp interface module. if C300.Initialize% then end if 'Set the CyberAmp device number. 'This step is not required if the device number is set to 'C300.DEVICENULL since this is the default.
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Page 114 PROGRAMMER'S GUIDE The following example program sets the gain, filter and coupling of channel 1 of the CyberAmp. 'The following INCLUDE statement is required to allow access to the routines that are exported by the C300LIB module. '$include: 'C300LIBB.INC' 'Initialize the CyberAmp interface module. if C300.Initialize% then end if 'Set the CyberAmp device number. 'This step is not required if the device number is set to 'C300.DEVICENULL since this is the default.
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PROGRAMMER'S GUIDE Page 115 if C300.SetCoupling% (1, C300.NEGINPUT, C300.COUPLINGDC) then print "Error setting CyberAmp - coupling:"; C300.GetLastError% end end if 'Now flush out the command queue to the CyberAmp. if C300.FlushCommands% then print "Error on flush command:"; C300.GetLastError% end end if 'Save the updated CyberAmp state into the EEPROM. 'This set is required if you wish to have the CyberAmp power up with the 'same settings the next time the unit is turned on. if C300.
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Page 116 PROGRAMMER'S GUIDE 5) If the investigator uses BNC cables to connect the CyberAmp 380 output to the input of a data acquisition interface, the CyberAmp channel numbers need not correspond to the interface channel numbers. Thus, a connections table should be maintained. In the ultimate case of intelligent support, the connections table could be automatically configured. To do so, the program sets the inputs of all CyberAmp 380 channels to ground and the gain to x1.
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SPECIFICATIONS Page 117 SPECIFICATIONS NUMBER CHANNELS ANALOG INPUTS Input signal range: Safe input voltage: Input resistance: Input capacitance: ANALOG OUTPUTS Output signal range: Output impedance: Output short-circuit duration: Output offset: Offset calibration: AMPLIFICATION Total gain: Gain accuracy: LOW-PASS FILTER Filter type: Selectable 3 dB frequencies: 8 ±10V DC minimum linear range. ±12 V typical working range. ±30 V power on. ±15 V power off. 1 MΩ. 45 pF.
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Page 118 SPECIFICATIONS NOTCH FILTER Frequency: Depth: -3 dB width: Tuneable from 45-70 Hz. 40 dB. 1 Hz. AC COUPLING Selectable coupling frequencies: 0.1, 1, 10, 30, 100, 300 Hz. DC OFFSET & AUTOZERO: DC offset adjustment: (input referred): Autozero lock-in range: ±3 Volts in 100 µV steps, pre-filter gain = x1 ±300 mV in 10 µV steps, pre-filter gain = x10 ±30 mV in 1 µV steps, pre-filter gain = x100 Same as DC offset adjustment ranges. NOISE Input noise: 0.1 Hz - 10 kHz: 0.1 Hz - 3 kHz: 0.
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SPECIFICATIONS OTHER FEATURES Electrode test: Page 119 ±0.5 V square wave applied simultaneously to all inputs via 1 MΩ resistors. For low-value source resistances, this corresponds to ±0.5 µA (1 µAp-p) current; frequency 10 Hz. Amplitude calibration waveform: 0 to +10.00 mV square wave at approximately 10 Hz. Overload indicators: Overload is detected if either the pre-filter or output amplifier output exceeds ±10.5 V. LED display remains on for 100 ms minimum.
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Page 120 Click mode: CONNECTORS Input BNC: Output BNC: Probe connection: Link connector: Chart recorder connector: RS-232 IN connector: RS-232 OUT connector: SPECIFICATIONS Signal directly applied to speaker. Bandwidth: 20 Hz to 5 kHz. Squelch range: Level below which tone suppressed: bipolar band centered at 0 V, with range 4 Vp-p. Internal speaker: 0.2 watts max. Phone jack: Suitable for headphones or external speaker (8 Ω). 0.2 watts maximum.
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SPECIFICATIONS Page 121 POWER AND DIMENSIONS Line voltage: 100-125 Vac or 200-250 Vac. User selectable by an external switch. 50-60 Hz. 30 watts. 0.5 A slow. 5 x 20 mm. 19-inch (483 mm) rack mount, 3.5 inch (89 mm) high. Depth 14 inches (356 mm) including handles. Depth 12.5 inches (317 mm) behind rack mount flanges. 8 lbs (3.5 kg). Line frequency: Power: Fuse: Cabinet dimensions: Net Weight: 5.
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Page 122 SPECIFICATIONS CHANNEL #5 OUTPUT CHANNEL #4 OUTPUT CHANNEL #6 OUTPUT CHANNEL #3 OUTPUT CHANNEL #7 OUTPUT CHANNEL #2 OUTPUT CHANNEL #8 OUTPUT CHANNEL #1 OUTPUT 8 7 15 6 14 5 13 4 12 3 2 11 10 1 9 NC ANALOG GROUND NC NC NC NC Figure 37. Pin connections of the DB15 female CHART RECORDER connector as viewed from the rear panel.
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REFERENCES Page 123 REFERENCES References Cain, C. & Welch, A.J. (1974) Thin-film temperature sensors for biological measurement. IEEE Trans. Biomed. Eng. BME-21(5), 421-423. Additional Reading Material Geddes, L.A. & Baker, L.E. (1989) Principles of Applied Biomedical Instrumentation. John Wiley & Sons: New York. Horowitz, P. and Hill, W., (1986). Measurements and signal processing. In. The Art of Electronics, Chapter 14. Cambridge. Cambridge University Press. Lemon, R. and Prochazka, A., ed. (1984).
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ADJUSTMENT PROCEDURES Page 125 ADJUSTMENT PROCEDURES There are very few adjustments that can be made inside the CyberAmp. The gain accuracy is determined by fixed, precision resistors, while the internal offsets are automatically corrected each time the unit is switched on and each time relevant settings, such as the gain, are changed. Tuning of the notch filter is the only adjustment that may be necessary to perform on a correctly functioning CyberAmp 380.
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Page 126 ADJUSTMENT PROCEDURES 2V 10 ms Figure 39. The upper trace shows the output during the notch test when the notch filter is badly tuned. The lower trace shows the output when the notch filter is correctly tuned. The output when the notch filter is tuned contains many harmonics. The vertical scaling is the same for both traces. The signal input was internally generated using the Notch Test command. Repeat the procedure for channels 2 to 8, adjusting trim potentiometers RP202 to RP802, respectively.
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CIRCUIT DIAGRAMS Page 127 CIRCUIT DIAGRAMS REQUEST FORM All the information that you require for operation of the CyberAmp 380 is included in the operator's manual. In the normal course of events, the CyberAmp 380 does not require any routine maintenance. Should you need the circuit diagrams for the CyberAmp 380, Axon Instruments will be pleased to supply them to you.
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SERIAL COMMUNICATION CABLES Page 129 SERIAL COMMUNICATIONS CABLES Most serial communications problems stem from an incorrectly wired cable furnished (at low cost) by some vendors. If using a PC compatible with either a 9-pin or a 25-pin D connector, we recommend purchase of an RS232-01 cable from Axon Instruments or a "null-modem" cable from a good vendor. This is the type of serial cable used to connect a computer to a pen plotter. It is not the type of cable normally used to connect a modem.
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LIST OF FIGURES AND TABLES Page 131 LIST OF FIGURES AND TABLES Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16 Fig. 17 Fig. 18 Fig. 19 Fig. 20 Fig. 21 Fig. 22 Fig. 23 Fig. 24 Fig. 25 Fig. 26 Fig. 27 Fig. 28 Fig. 29 Fig. 30 Fig. 31 Fig. 32 Fig. 33 Fig. 34 Fig. 35 Fig. 36 Fig. 37 Fig. 38 Fig. 39 Safety symbols Signal processing pathway ...............................................................................................
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WARRANTY Page 133 WARRANTY Axon Instruments warrants its non-consumable hardware products to be free from defects in materials and workmanship for 12 months from date of invoice. We will repair or replace without cost to the customer any of these products that are defective and which are returned to our factory properly packaged with transportation charges prepaid. We will pay for the return shipping of the product to the customer.
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WARNING Page 135 WARNING Shipping the CyberAmp and AI 400 SmartProbes The CyberAmp is a solidly built instrument designed to survive shipping around the world. However, in order to avoid damage during shipping, the CyberAmp must be properly packaged. In general, the best way to package the CyberAmp is in the original factory carton. If this is no longer available, we recommend that you carefully wrap the CyberAmp in at least three inches (75 mm) of foam or "bubble-pack" sheeting.
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INDEX Page 137 A/D interface, 15 AC coupling, 26 Adjustment Procedures, 125 AI Series Probes AI 401, 47, 51 AI 402, 47, 51 AI 417, 46 AI 490, 57 Amplification, 26 Amplifier differential, 60 gain, 7 audio monitor, 13 Audio monitor, 8 Audio Monitor, 32 Automatic offset calibration, 7 Autozeroing, 26 Axon Expandable RS-232 Bus, 94 high-pass, 26 low-pass, 23 notch, 30, 125 Force, 49 Functional checkout, 11 CMD300, 65 Command Reference, 69 Command-File Mode, 68 Command-Line Mode, 67 Common-Mode Rejection, 39
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