SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE Notice While reasonable efforts have been made to assure the accuracy of this document, Telit assumes no liability resulting from any inaccuracies or omissions in this document, or from use of the information obtained herein. The information in this document has been carefully checked and is believed to be entirely reliable. However, no responsibility is assumed for inaccuracies or omissions.
Usage and Disclosure Restrictions License Agreements The software described in this document is the property of Telit and its licensors. It is furnished by express license agreement only and may be used only in accordance with the terms of such an agreement. Copyrighted Materials Software and documentation are copyrighted materials. Making unauthorized copies is prohibited by law.
Contents 1. INTRODUCTION ......................................................................................................................................................... 7 1.1. 1.2. 1.3. 1.4. 1.5. 1.6. SCOPE ....................................................................................................................................................................... 7 AUDIENCE ..................................................................................................................
10. AUDIO SECTION OVERVIEW ................................................................................................................................ 50 10.1. ELECTRICAL CHARACTERISTICS ............................................................................................................................. 51 10.1.1. Input Lines ..................................................................................................................................................... 51 10.1.2.
1. Introduction 1.1. Scope The aim of this document is the description of some hardware solutions useful for developing a product with the Telit GE865 module. 1.2. Audience This document is intended for Telit customers, who are integrators, about to implement their applications using our GE865 modules. 1.3. Contact Information, Support For general contact, technical support, to report documentation errors and to order manuals, contact Telit’s Technical Support Center (TTSC) at: TS-EMEA@telit.
1.4. Document Organization This document contains the following chapters: Chapter 1: “Introduction” provides a scope for this document, target audience, contact and support information, and text conventions. Chapter 2: “Overview” provides an overview of the document. Chapter 3: “GE865 Mechanical Dimensions” Chapter 4: “GE865 Module Connections” deals with the pin out configuration and layout. Chapter 5: “Hardware Commands” How to operate on the module via hardware.
1.5. Text Conventions Danger – This information MUST be followed or catastrophic equipment failure or bodily injury may occur. Caution or Warning – Alerts the user to important points about integrating the module, if these points are not followed, the module and end user equipment may fail or malfunction. Tip or Information – Provides advice and suggestions that may be useful when integrating the module. All dates are in ISO 8601 format, i.e. YYYY-MM-DD. 1.6.
2. Overview The aim of this document is the description of some hardware solutions useful for developing a product with the Telit GE865 module. In this document all the basic functions of a mobile phone will be taken into account; for each one of them a proper hardware solution will be suggested and eventually the wrong solutions and common errors to be avoided will be evidenced. Obviously this document cannot embrace the whole hardware solutions and products that may be designed.
3. GE865 Mechanical Dimensions The GE865-QUAD overall dimensions are: Length: Width: Thickness: Weight: 22 mm 22 mm 3.
4. GE865 module connections 4.1. PIN-OUT Ball Signal I/O Function Note Type Audio E8 EAR- AO Earphone signal output, phase - Audio D8 EAR+ AO Earphone signal output, phase + Audio B8 MIC+ AI Mic.signal input; phase+ Audio C8 MIC- AI Mic.
Ball Signal I/O D3 GPIO_01 / DVI_WA0 I/O D2 GPIO_02 / JDR / DVI_RX I/O E4 GPIO_03 / DVI_TX I/O H7 GPIO_04 / TX_DISAB I/O G2 GPIO_05 / RFTXMON I/O H8 GPIO_06 / ALARM I/O G6 GPIO_07 / BUZZER I/O D4 GPIO_08 / DVI_CLK I/O Function Note GPIO GPIO01 Configurable GPIO / Digital Audio Interface (WA0) GPIO02 I/O pin / Jammer Detect Report / Digital Audio Interface (RX) GPIO03 GPIO I/O pin // Digital Audio Interface (TX) GPIO04 Configurable GPIO / TX Disable input GPIO05 Configurable GPIO
WARNING:Reserved pins must not be connected. NOTE: If not used, almost all pins should be left disconnected.
4.1.1.
5. Hardware Commands 5.1. Turning ON the GE865 To turn on the GE865 the pad ON# must be tied low for at least 1 second and then released. When the power supply voltage is lower than 3.4V the pad ON# must be tied low at least 5 seconds. The maximum current that can be drained from the ON# pad is 0,1 mA. A simple circuit to do it is: NOTE: Don't use any pull up resistor on the ON# line, it is internally pulled up.
A flow chart showing the proper turn on procedure is displayed below: Modem ON Proc. Y PWMON = ON? DELAY= 900mSec N Enter AT ON_OFF = LOW Y Delay = 5 Sec AT answer in 1Sec ? ON_OFF = HIGH N N PWMON = ON? AT init sequence. Modem RESET Proc. Y Delay 1s Start AT CMD. NOTE: In order to avoid a back powering effect it is recommended to avoid having any HIGH logic level signal applied to the digital pins of the GE865 when the module is powered off or during an ON/OFF transition.
A flow chart showing the AT command managing procedure is displayed below: Start AT CMD. DELAY= 300mSec Enter AT Y AT answer in 1Sec ? N Disconnect VBatt Modem ON Proc. AT init sequence.
For example: 1- Let's assume you need to drive the ON# pad with a totem pole output of a +3/5 V microcontroller (uP_OUT1): 2- Let's assume you need to drive the ON# pad directly with an ON/OFF button:
5.2. Turning OFF the GE865 Turning off of the device can be done in two ways: via AT command (see GE865 Software User Guide, AT#SHDN) by tying low pin ON# Either ways, the device issues a detach request to network informing that the device will not be reachable any more. To turn OFF the GE865 the pad ON# must be tied low for at least 2 seconds and then released. A Pulse duration less than 2 seconds should also start the power off procedure, but this is not guaranteed.
The following flow chart shows the proper turnoff procedure: Modem OFF Proc. N PWMON = ON? Y ON_OFF = LOW Delay = 2 Sec ON_OFF = HIGH N Modem ON Proc.
5.3. Resetting the GE865 5.3.1. Hardware Unconditional restart WARNING: The hardware unconditional Restart must not be used during normal operation of the device since it does not detach the device from the network. It shall be kept as an emergency exit procedure to be done in the rare case that the device gets stacked waiting for some network or SIM responses. To unconditionally reboot the GE865, the pad RESET# must be tied low for at least 200 milliseconds and then released.
In the following flow chart is detailed the proper restart procedure: Modem Reset Proc. Reset# = LOW Delay 200ms Reset# = HIGH N PWRMON = ON Delay 1s Modem ON Proc. Y Delay 1s Start AT CMD. NOTE: In order to avoid a back powering effect it is recommended to avoid having any HIGH logic level signal applied to the digital pins of the GE865 when the module is powered off or during an ON/OFF transition.
For example: 1.
6. Power Supply The power supply circuitry and board layout are a very important part in the full product design and they strongly reflect on the product overall performances, hence read carefully the requirements and the guidelines that will follow for a proper design. 6.1.
6.2.
6.2.1. Power consumption Plots This document section is showing the typical Current consumption plots (using Agilent 66319D) in the normal working conditions of the module.
GSM900 – GPRS Call – Power level 5 - 1 Slot TX GSM900 – GPRS Call – Power level 5 - 2 Slot TX, 3 Slot RX
DCS1800 – Voice Call – Power level 0 DCS1800 – GPRS Call – Power level 0 – 1 Slot TX
PCS1900 – GPRS Call – Power level 0 - 2 Slot TX, 3 Slot RX
6.3. General Design Rules The principal guidelines for the Power Supply Design embrace three different design steps: the electrical design the thermal design the PCB layout. 6.3.1. Electrical Design Guidelines The electrical design of the power supply depends strongly from the power source where this power is drained. We will distinguish them into three categories: +5V input (typically PC internal regulator output) +12V input (typically automotive) Battery 6.3.1.1.
6.3.1.2. + 12V input Source Power Supply Design Guidelines The desired output for the power supply is 3.8V, hence due to the big difference between the input source and the desired output, a linear regulator is not suited and shall not be used. A switching power supply will be preferable because of its better efficiency especially with the 2A peak current load represented by the GE865.
6.3.1.3. Battery Source Power Supply Design Guidelines The desired nominal output for the power supply is 3.8V and the maximum voltage allowed is 4.2V, hence a single 3.7V Li-Ion cell battery type is suited for supplying the power to the Telit GE865 module. WARNING: The three cells Ni/Cd or Ni/MH 3,6 V Nom. battery types or 4V PB types MUST NOT BE USED DIRECTLY since their maximum voltage can rise over the absolute maximum voltage for the GE865 and damage it.
6.3.2.
6.3.3. Power Supply PCB layout Guidelines As seen on the electrical design guidelines the power supply shall have a low ESR capacitor on the output to cut the current peaks and a protection diode on the input to protect the supply from spikes and polarity inversion. The placement of these components is crucial for the correct working of the circuitry. A misplaced component can be useless or can even decrease the power supply performances.
7. Antenna The antenna connection and board layout design are the most important aspect in the full product design as they strongly affect the product overall performances, hence read carefully and follow the requirements and the guidelines for a proper design. 7.1.
conjunction with any other antenna or transmitter. If antenna is installed with a separation distance of less than 20 cm from all persons or is co-located or operating in conjunction with any other antenna or transmitter then additional FCC/IC testing may be required. End-Users must be provided with transmitter operation conditions for satisfying RF exposure compliance. Antennas used for this OEM module must not exceed 3dBi gain for mobile and fixed operating configurations. 7.2.
7.3. PCB Guidelines in case of FCC certification In the case FCC certification is required for an application using GE865, according to FCC KDB 996369 for modular approval requirements, the transmission line has to be similar to that implemented on GE865 interface board and described in the following chapter. 7.3.1.
7.3.2. Transmission line measurements HP8753E VNA (Full-2-port calibration) has been used in this measurement session. A calibrated coaxial cable has been soldered at the pad corresponding to GE865 RF output; a SMA connector has been soldered to the board in order to characterize the losses of the transmission line including the connector itself. During Return Loss / impedance measurements, the transmission line has been terminated to 50 Ω load.
Line input impedance (in Smith Chart format, once the line has been terminated to 50 Ω load) is shown in the following figure: Insertion Loss of G-CPW line plus SMA connector is shown below:
7.4. GSM Antenna - Installation Guidelines Install the antenna in a place covered by the GSM signal.
8. Logic level specifications Where not specifically stated, all the interface circuits work at 2.8V CMOS logic levels. The following table shows the logic level specifications used in the GE865 interface circuits: Absolute Maximum Ratings -Not Functional Parameter Min Max Input level on any digital pin -0.3V +3.1V (CMOS 2.8) when on Input level on any digital pin -0.3V +2.1V (CMOS 1.8) when on Input voltage on analog pins when -0.3V +3.0 V on Operating Range - Interface levels (2.
8.1. Reset signal Signal RESET# Function Phone reset I/O I Bga Ball C1 RESET# is used to reset the GE865 . Whenever this signal is pulled low, the GE865 is reset. When the device is reset it stops any operation. After the release of the reset GE865 is unconditionally shut down, without doing any detach operation from the network where it is registered. This behaviour is not a proper shut down because any GSM device is requested to issue a detach request on turn off.
9. Serial Ports The serial port on the GE865 is the core of the interface between the module and OEM hardware. 2 serial ports are available on the module: MODEM SERIAL PORT 1 (Main, ASC0) MODEM SERIAL PORT 2 (Auxiliary, ASC1) 9.1. MODEM SERIAL PORT Several configurations can be designed for the serial port on the OEM hardware, but the most common are: RS232 PC com port microcontroller UART @ 2.
The signals of the GE865 serial port are: RS232 Pin Number Signal GE865 Pad Number Name 1 DCD - dcd_uart B5 Data Carrier Detect A4 Transmit line *see Note Output transmit line of GE865 UART A3 Receive line *see Note Input receive of the GE865 UART DTR - dtr_uart B3 Data Terminal Ready Input to the GE865 that controls the DTE READY condition 5 GND C2, C7, E5, E7, G1, G3, G4, G5, H3, H6 Ground 6 DSR - dsr_uart B2 Data Set Ready 7 RTS -rts_uart A1 Request to Send 8 CTS - cts_uart
9.2. RS232 level translation In order to interface the GE865 with a PC com port or a RS232 (EIA/TIA-232) application a level translator is required. This level translator must: invert the electrical signal in both directions; change the level from 0/2.8V to +15/-15V . Actually, the RS232 UART 16450, 16550, 16650 & 16750 chipsets accept signals with lower levels on the RS232 side (EIA/TIA-562), allowing a lower voltage-multiplying ratio on the level translator.
An example of level translation circuitry of this kind is: The example is done with a SIPEX SP3282EB RS232 Transceiver that could accept supply voltages lower than 3V DC. NOTE: In this case Vin has to be set with a value compatible with the logic levels of the module. (Max 2.9V DC). In this configuration the SP3282EB will adhere to EIA/TIA-562 voltage levels instead of RS232 (-5 ~ +5V).
Second solution could be done using a MAXIM transceiver (MAX218) In this case the compliance with RS232 (+-5V) is possible. Another level adapting method could be done using a standard RS232 Transceiver (MAX3237EAI) adding some resistors to adapt the levels on the GE865 Input lines. NOTE: In this case has to be taken in account the length of the lines on the application to avoid problems in case of High-speed rates on RS232.
5V UART level translation If the OEM application uses a microcontroller with a serial port (UART) that works at a voltage different from 2.8 - 3V, then a circuitry has to be provided to adapt the different levels of the two set of signals. As for the RS232 translation there are a multitude of single chip translators. For example a possible translator circuit for a 5V TRANSMITTER/RECEIVER can be: TIP: Note that the TC7SZ07AE has open drain output; therefore the resistor R2 is mandatory.
10. Audio Section Overview The Base Band Chip of the GE865 provides one audio path both in Uplink (transmit) and in Downlink (receive) direction , as shown in the next figure . For more information refer to Telit document : “ 80000NT10007a Audio Settings Application Note “.
10.1. Electrical Characteristics TIP: Being the microphone circuitry the more noise sensitive, its design and layout must be done with particular care. Both microphone paths are balanced and the OEM circuitry must be balanced designed to reduce the common mode noise typically generated on the ground plane. However the customer can use the unbalanced circuitry for particular application. 10.1.1.
10.1.2. Output Lines TIP : We suggest driving the load differentially , thus the output swing will double and the need for the big output coupling capacitor avoided. However if particular OEM application needs, also a Single Ended (S.E) circuitry can be implemented but the output power will be reduced four times. The OEM circuitry shall be designed to reduce the common mode noise typically generated on the ground plane,getting the maximum power output from the device (low resistance tracks). WARNING.
11. General Purpose I/O The general purpose I/O pads can be configured to act in three different ways: input output alternate function (internally controlled) Input pads can only be read ; they report the digital value (high or low) present on the pad at the read time . Output pads can only be written or queried and set the value of the pad output. An alternate function pad is internally controlled by the GE865 firmware and acts depending on the function implemented.
11.1. GPIO Logic levels Where not specifically stated, all the interface circuits work at 2.8V CMOS logic levels. The following table shows the logic level specifications used in the GE865 interface circuits: Absolute Maximum Ratings -Not Functional Parameter Min Max Input level on any digital pin -0.3V +3.1V when on (CMOS 2.8) Input level on any digital pin -0.3V +2.1V when on (CMOS 1.8) Input voltage on analog pins -0.3V +3.0V when on Operating Range - Interface levels (2.
11.2. Using a GPIO Pad as INPUT The GPIO pads, when used as inputs, can be connected to a digital output of another device and report its status, provided this device has interface levels compatible with the 2.8V CMOS levels of the GPIO. If the digital output of the device to be connected with the GPIO input pad has interface levels different from the 2.8V CMOS, then it can be buffered with an open collector transistor with a 47K pull up to 2.8V.
11.5. Using the RFTXMON Output GPIO5 The GPIO5 pin, when configured as RFTXMON Output, is controlled by the GE865 module and will rise when the transmitter is active and fall after the transmitter activity is completed. There are 2 different modes for this function: 1) Active during all the calls: For example, if a call is started, the line will be HIGH during all the conversation and it will be again LOW after hanged up.
TR2 SMBT2907A +V buzzer R1 4,7K D1 D1N4148 C1 33pF + - R2 1K GPIO7 TR1 BCR141W NOTE: To correctly drive a buzzer a driver must be provided, its characteristics depend on the Buzzer and for them refer to your buzzer vendor. 11.8. Indication of network service availability The STAT_LED pin status shows information on the network service availability and Call status. In the GE865 modules, the STAT_LED usually needs an external transistor to drive an external LED.
11.9. RTC Bypass out The VRTC pin brings out the Real Time Clock supply, which is separate from the rest of the digital part, allowing having only RTC going on when all the other parts of the device are off. To this power output a backup capacitor can be added in order to increase the RTC autonomy during power off of the battery. NO Devices must be powered from this pin. 11.10. External SIM Holder Implementation Please refer to the related User Guide (SIM Holder Design Guides, 80000NT10001a).
12. DAC and ADC section 12.1. DAC Converter 12.1.1. Description The GE865 provides a Digital to Analog Converter. The signal (named DAC_OUT) is available on BGA Ball G7 of the GE865 and on pin 17 of PL102 on GE865 Interface Board (CS1324). The on board DAC is a 10 bit converter, able to generate a analogue value based a specific input in the range from 0 up to 1023.
12.1.2. Enabling DAC An AT command is available to use the DAC function. The command is: AT#DAC= [ [, ]] - scale factor of the integrated output voltage (0..1023 - 10 bit precision) it must be present if =1 Refer to SW User Guide or AT Commands Reference Guide for the full description of this function. NOTE: The DAC frequency is selected internally. D/A converter must not be used during POWERSAVING. 12.1.3.
12.2. ADC Converter 12.2.1. Description The on board A/D are 11-bit converter. They are able to read a voltage level in the range of 0÷2 volts applied on the ADC pin input, store and convert it into 11 bit word. Input Voltage range AD conversion Resolution Min 0 - Max 2 11 <1 Units Volt bits mV The GE865 module provides 2 Analog to Digital Converters. The input lines are: ADC_IN1 available on Ball F5 and Pin 19 of PL102 on GE865 Interface Board (CS1324).
13. Mounting the GE865 on your Board 13.1. General The GE865 modules have been designed in order to be compliant with a standard lead-free SMT process. 13.2.
13.3. Recommended foot print for the application I n order to easily rework the GE865 is suggested to consider on the application a 1.5mm Inhibit area around the module. It is also suggested, as common rule for an SMT component, to avoid having a mechanical part of the application in direct contact with the module. NOTE: In the customer application, the region under INHIBIT WIRING *1 (see figure) must be clear from signal or ground paths.
13.4. Debug of the GE865 in production To test and debug the mounting of the GE865, we strongly recommend to foreseen test pads on the host PCB, in order to check the connection between the GE865 itself and the application and to test the performance of the module connecting it with an external computer. Depending by the customer application, these pads include, but are not limited to the following signals: TXD RXD ON/OFF RESET GND VBATT TX_AUX RX_AUX PWRMON SERVICE 13.5.
13.6. PCB pad design Non solder mask defined” (NSMD) type is recommended for the solder pads on the PCB. Recommendations for PCB pad dimensions Ball pitch [mm] Solder resist opening diameter A [mm] Metal pad diameter B [mm] 2,4 1,150 1 ± 0.05 It is not recommended to place via or microvia not covered by solder resist in an area of 1,6mm diameter around the pads unless it carries the same signal of the pad itself. (see following figure).
Holes in pad are allowed only for blind holes and not for through holes. Recommendations for PCB pad surfaces: Finish Electro-less Ni / Immersion Au Layer thickness [µm] 3 –7 / 0.05 – 0.15 Properties good solder ability protection, high shear force values The PCB must be able to resist the higher temperatures which are occurring at the lead-free process. This issue should be discussed with the PCB-supplier.
13.7.1.
NOTE: All temperatures refer to topside of the package, measured on the package body surface WARNING: The GE865 module withstands one reflow process only.
14. Packing system 14.1. Packing on tray The GE865 modules are packaged on trays of 50 pieces each. This is especially suitable for the GE865 according to SMT processes for pick & place movement requirements. See detail B for module positioning and tray orientation into the envelope.
14.1.1. Tray detail The size of the tray is: 329 x 176mm. WARNING: These trays can withstand at the maximum temperature of 65° C.
14.2. Packaging on reel The GE865-QUAD can be packaged on reels of 200 pieces each. See figure for module positioning into the carrier. DIRECTION OF UNREELING NOT Rounded Corner 14.2.1.
14.2.2.
14.2.3. Packaging detail Silica-gel bag (x3) Shielding & ESD envelope Humidity indicator Multi Device & Packaging label Reel label TOTAL: 200 MODULES 14.3. Moisture sensibility The level of moisture sensibility of the Product is “3”, according with standard IPC/JEDEC JSTD-020, take care of all the relative requirements for using this kind of components.
15. Conformity Assessment Issues The Telit GE865 Module has been assessed in order to satisfy the essential requirements of the R&TTE Directive 1999/05/EC (Radio Equipment & Telecommunications Terminal Equipments) to demonstrate the conformity against the harmonised standards with the final involvement of a Notified Body. 0889 By using our certified module, the evaluation under Article 3.
• Users and installers must be provided with antenna installation instructions and transmitter operating conditions for satisfying RF exposure compliance. Manufacturers of mobile, fixed or portable devices incorporating this module are advised to clarify any regulatory questions and to have their complete product tested and approved for FCC compliance.
16. SAFETY RECOMMANDATIONS READ CAREFULLY Be sure the use of this product is allowed in the country and in the environment required. The use of this product may be dangerous and has to be avoided in the following areas: Where it can interfere with other electronic devices in environments such as hospitals, airports, aircrafts, etc. Where there is risk of explosion such as gasoline stations, oil refineries, etc.
17.