November ’00 Preface Series 2000 Reader System Mini-RFM RI-RFM-003B Reference Guide 11-06-29-030 November 2000 1
Mini-RFM - Reference Guide November ’00 Edition Three - November 2000 This is the third edition of this manual, it describes the following equipment: TIRIS Mini-Radio Frequency Module RI-RFM-003B Texas Instruments (TI) reserves the right to make changes to its products or services or to discontinue any product or service at any time without notice. TI provides customer assistance in various technical areas, but does not have full access to data concerning the use and applications of customer's products.
PREFACE Read This First About This Guide This manual describes the TIRIS Mini-Radio Frequency Module (Mini-RFM), it provides the information that you will need in order to install the Mini-RFM into your RFID system. It is generally targeted at systems integrators or value added resellers. Regulatory, safety and warranty notices that must be followed are given in Chapter 6.
Mini-RFM - Reference Guide November ’00 Document Overview Chapter 1: 1.1 1.2 1.3 1.4 Chapter 2: 2.1 2.2 2.3 2.4 Chapter 3: 3.1 3.2 3.3 Chapter 4: 4.1 4.2 4.3 4.4 Chapter 5: 5.1 5.2 5.3 5.4 5.5 5.6 Chapter 6: 6.1 6.2 6.3 6.4 Page Product Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 General............................................................................................... 6 System Overview ..............................................................
CHAPTER 1 Introduction Chapter 1: Product Description This chapter introduces you to the Mini-RFM. It tells you what the module is for, provides an overview of the complete system and the product itself. It also provides a mechanical description of the construction of the Mini-RFM. Topic Page 1.1 General..........................................................................................................6 1.2 System Overview ..........................................................................
Mini-RFM - Reference Guide 1.1 November ’00 General This manual provides information about the TIRIS Mini-Radio Frequency Module RIRFM-003B. It describes the module and how to integrate it into your RFID system. This guide should be used in conjunction with the RFM Sequence Control Reference Manual (document number 11-06-21-049) which describes the timing and sequence of radio communications between the TIRIS transponder and the radio frequency module. 1.
November ’00 Chapter 1. Introduction Its small size and low supply voltage makes the Mini-RFM well suited for portable Reading/Writing Units, as well as for stationary equipment where medium read/write range and speed is sufficient. The data input and output lines are compatible with the HCMOS- logic family. 1.4 Mechanical Construction The RF module has a simple mechanical construction where all the components are mounted on the Printed Circuit Board (PCB).
CHAPTER 2 Electrical Description Chapter 2: Functional Description This chapter provides an electrical description to block diagram level of how the MiniRFM works. Topic Page 2.1 General..........................................................................................................9 2.2 Transmitter ...................................................................................................9 2.3 Receiver ...................................................................................
November ’00 2.1 Chapter 2. Electrical Description General The RF module is the interface between the TIRIS transponder and the data processing unit of a TIRIS Reader. It contains circuitry to: - send a charge-up signal to a TIRIS transponder - program a read/write transponder - to receive the signal from the transponder and to prepare the received signal for digital decoding.
Mini-RFM - Reference Guide November ’00 Figure 2: Mini-RFM Block Diagram 10
November ’00 2.3 Chapter 2. Electrical Description Receiver The receiver comprises three parts: the RF part, the interface and the logic. The selective amplifier in the RF Part of the receiver: - amplifies the RF signal received from the antenna circuit, then - demodulates the FSK signal from the TIRIS transponder, and - generates an analog voltage (RSSI) that provides an indication of the received signal strength.
Mini-RFM - Reference Guide November ’00 Figure 3: Mini-RFM’s Antenna Circuit 12
CHAPTER 3 Connectors Chapter 3: Connectors This chapter contains a listing of the module’s two connectors (ST1 and ST2) together with a list of the signals contained on each pin. Topic Page 3.1 Connector Location ...................................................................................14 3.2 Connector ST1............................................................................................15 3.3 Connector ST2..............................................................................
Mini-RFM - Reference Guide 3.1 November ’00 Connector Location Figure 4 and Figure 5 show the location of the terminals on the PCB from the top and from the bottom.
November ’00 3.2 Chapter 3.
Mini-RFM - Reference Guide 3.3 November ’00 Connector ST2 Table 2: Antenna Tuning Connector - ST2 3.
CHAPTER 4 Specifications Chapter 4: Specifications This chapter provides the specific details that you will need in order to use the TIRIS Mini-Radio Frequency Module RI-RFM-003B correctly. It includes general data, electrical characteristics, timing characteristics and mechanical data. Topic Page 4.1 Recommended Operating Conditions......................................................18 4.2 Electrical Characteristics ..........................................................................18 4.
Mini-RFM - Reference Guide 4.1 November ’00 Recommended Operating Conditions Operating free-air temperature range.......................... 0 to +50 °C Storage temperature range........................................ -25 to +85 °C Note: Free-air temperature: air temperature immediately surrounding the Mini-RFM. If the module is incorporated into a housing, it must be guaranteed by proper design or cooling that the internal temperature does not exceed the ratings given here. Parameter 4.
November ’00 Chapter 4. Specifications Description I_IL Low level input current for RSCA and RSCB V_IL=0V 17, 19 I_IH High level input current for RSCA and RSCB V_IH=5V 17, 19 V_OH High level output voltage for RXCK, RXDT and RXSS- I_OH=-2mA V_OH High level output voltage for RXCK, RXDT and RXSS- V_OL Low level output voltage for RXCK, RXDT and RXSS- R_GND Decoupling resistor between GNDL and GNDP Parameter Condition Pin No. of ST1 Parameter Description min. nom.
Mini-RFM - Reference Guide 4.3 November ’00 Timing Characteristics at Tamb=0-50 °C, VSRL=5.0 V, VSP=5.0 V Parameter Description Condition Pin No. of ST1 min. nom. max. Unit f_TX Transmitter frequency - A1 134.1 134.2 134.3 kHz f_OSC Internal oscillator frequency - - - 4294.4 - kHz f_mRX Center frequency of receiver - - - 128.
November ’00 4.4 Chapter 4. Specifications Mechanical Data Length......................................................................... Width........................................................................... Height, body................................................................ Height, at connector.................................................... Weight......................................................................... 60.2 mm 55.1 mm 10.4 mm 11.
CHAPTER 5 Installation and Use Chapter 5: Installation and Use This chapter provides the specific details that you will need in order to install the TIRIS Mini-RFM correctly. It includes a detailed description of the power supply requirements, the antenna characteristics, the connecting cable and how to tune the antenna to resonance. Topic Page 5.1 Mechanical Mounting............................................................................... 23 5.2 Supply Voltage ...............................
November ’00 5.1 Chapter 5. Installation and Use Mechanical Mounting To protect the RF module from strong mechanical shock and vibration, grommets are inserted into the mounting hole of the PCB as shown in Figure 9. Because the grommets are made of soft material, eyelets or spacers must be inserted into them when the RF module is mounted with screws.
Mini-RFM - Reference Guide November ’00 Figure 10 shows an example of how to supply the RF module in a battery supplied reading unit where short lines are possible. Figure 11 shows an example of how to wire a stationary application where long supply lines (over 15 cm) are used. The capacitor C_E1 between the VSP and GNDP pins is necessary to reduce the RF ripple voltage and EMI on the supply line and must have low impedance at the transmit frequency (ESR = Equivalent Serial Resistor).
November ’00 Chapter 5. Installation and Use Figure 11: Supply Line Wiring for a Separated Power Supply 5.3 Receiver Signal Strength Output RXSSIf you are going to operate more than one TIRIS reader in a local area, the systems should be synchronized to each other. An intelligent control unit achieves this synchronization by sampling for the presence or absence of the field strength indicator signal RXSS-. A power pulse in the area will cause RXSS- to be active.
Mini-RFM - Reference Guide November ’00 Figure 12: Synchronization output Control - Digital Adjustment An analog adjustment of the sensitivity level can be realized if a potentiometer is used as shown in Figure 13 or if a variable voltage source is used to bias one or both of the control inputs RSCA and RSCB.
November ’00 5.4 Chapter 5. Installation and Use Programming a Transponder To write data to a read/write transponder the transmitter of the RF module must be switched off and on periodically after the power pulse is completed. As shown in Figure 14 each data bit has the same length t_bit, but the duration t_offL or t_offH during which the transmitter is switched off, determines the value of the bit.
Mini-RFM - Reference Guide November ’00 d. Noise, i.e. magnetic interference energy in or close to the TIRIS frequency range can reduce the read range remarkably. Sources of interference can be, for example: electronic equipment with built-in switch mode power supplies, monitors and TV-sets with their magnetic deflection, which are not shielded enough. In such conditions you may be able to obtain better read/write ranges with a smaller antenna rather than a large one.
November ’00 5.6 Chapter 5. Installation and Use Antenna Tuning In order to get all the available field strength from the antenna, it must be tuned to resonance. To do this, the following set-up and equipment are required. 5.6.1 To Switch-ON the Transmitter The reading/writing unit or test set up should be able to switch the RF module’s transmitter to a fast repeating reading mode or continuous wave mode.
Mini-RFM - Reference Guide 5.6.4 November ’00 Tuning Procedure WARNING: CARE MUST BE TAKEN WHEN HANDLING THE MINI-RFM. HIGH VOLTAGE ACROSS THE ANTENNA TERMINALS AND TUNING CONNECTORS COULD BE HARMFUL TO YOUR HEALTH. IF THE ANTENNA INSULATION IS DAMAGED IT MUST NOT BE CONNECTED TO THE MINI-RFM. Ensure that the reader is switched OFF. Connect the antenna to the RF Module. Remove all jumpers from the tuning connector ST2 and connect the “Switch Box” with all six switches in the OFF position.
CHAPTER 6 Warnings, Cautions and Notices Chapter 6: Warnings, Cautions and Notices This chapter provides the Warnings, Cautions and Notices that are relevant to the Mini-RFM. Topic Page 6.1 FCC / Telecommunications Regulations .................................................32 6.2 Important Note to Purchasers/Users of the Mini-RFM in the USA ........32 6.3 Warning.......................................................................................................32 6.4 Cautions......................
Mini-RFM - Reference Guide 6.1 November ’00 FCC / Telecommunications Regulations The TIRIS RF Module generates RF emissions at 134.2 kHz. The radiation of the fundamental and the harmonics will vary with the type of antenna and other devices or functions connected to the RF module. The required FCC or Telecommunications approvals must be obtained prior to operating the TIRIS RF Module with antenna(s), power supply and a control module or other devices.
November ’00 Chapter 6. Warnings, Cautions and Abbreviations The transmitter power output stage can be damaged, if the antenna terminal A1 has a short circuit either to the ground or to the supply voltage and no current limitation is applied. The transmitter power output stage can operate only with a limited duty cycle. This subject needs to be given attention especially during the antenna tuning procedure. The ground pins GNDL and GNDP have to be connected externally to avoid damage to the RF Module.
Mini-RFM - Reference Guide November ’00 34
