SLOS757G December   2011  – March 2020 TRF7962A

PRODUCTION DATA.  

  1. 1Device Overview
    1. 1.1 Features
    2. 1.2 Applications
    3. 1.3 Description
    4. 1.4 Application Block Diagram
  2. 2Revision History
  3. 3Device Characteristics
    1. 3.1 Related Products
  4. 4Terminal Configuration and Functions
    1. 4.1 Pin Diagrams
    2. 4.2 Signal Descriptions
  5. 5Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Electrical Characteristics
    5. 5.5 Thermal Resistance Characteristics
    6. 5.6 Switching Characteristics
  6. 6Detailed Description
    1. 6.1  Functional Block Diagram
    2. 6.2  Power Supplies
    3. 6.3  Supply Arrangements
    4. 6.4  Supply Regulator Settings
    5. 6.5  Power Modes
    6. 6.6  Receiver – Analog Section
      1. 6.6.1 Main and Auxiliary Receiver
      2. 6.6.2 Receiver Gain and Filter Stages
    7. 6.7  Receiver – Digital Section
      1. 6.7.1 Received Signal Strength Indicator (RSSI)
        1. 6.7.1.1 Internal RSSI – Main and Auxiliary Receivers
        2. 6.7.1.2 External RSSI
    8. 6.8  Oscillator Section
    9. 6.9  Transmitter - Analog Section
    10. 6.10 Transmitter - Digital Section
    11. 6.11 Transmitter – External Power Amplifier or Subcarrier Detector
    12. 6.12 Communication Interface
      1. 6.12.1 General Introduction
      2. 6.12.2 FIFO Operation
      3. 6.12.3 Parallel Interface Mode
      4. 6.12.4 Reception of Air Interface Data
      5. 6.12.5 Data Transmission to MCU
      6. 6.12.6 Serial Interface Communication (SPI)
        1. 6.12.6.1 Serial Interface Mode Without Slave Select (SS)
        2. 6.12.6.2 Serial Interface Mode With Slave Select (SS)
      7. 6.12.7 Direct Mode
    13. 6.13 Direct Commands from MCU to Reader
      1. 6.13.1  Command Codes
      2. 6.13.2  Reset FIFO (0x0F)
      3. 6.13.3  Transmission With CRC (0x11)
      4. 6.13.4  Transmission Without CRC (0x10)
      5. 6.13.5  Transmit Next Time Slot (0x14)
      6. 6.13.6  Block Receiver (0x16)
      7. 6.13.7  Enable Receiver (0x17)
      8. 6.13.8  Test Internal RF (RSSI at RX Input With TX On) (0x18)
      9. 6.13.9  Test External RF (RSSI at RX Input With TX Off) (0x19)
      10. 6.13.10 Register Preset
    14. 6.14 Register Description
      1. 6.14.1 Register Overview
        1. 6.14.1.1 Main Configuration Registers
          1. 6.14.1.1.1 Chip Status Control Register (0x00)
          2. 6.14.1.1.2 ISO Control Register (0x01)
        2. 6.14.1.2 Protocol Subsetting Registers
          1. 6.14.1.2.1 TX Pulse Length Control Register (0x06)
          2. 6.14.1.2.2 RX No Response Wait Time Register (0x07)
          3. 6.14.1.2.3 RX Wait Time Register (0x08)
          4. 6.14.1.2.4 Modulator and SYS_CLK Control Register (0x09)
          5. 6.14.1.2.5 RX Special Setting Register (0x0A)
          6. 6.14.1.2.6 Regulator and I/O Control Register (0x0B)
        3. 6.14.1.3 Status Registers
          1. 6.14.1.3.1 IRQ Status Register (0x0C)
          2. 6.14.1.3.2 Collision Position and Interrupt Mask Registers (0x0D and 0x0E)
          3. 6.14.1.3.3 RSSI Levels and Oscillator Status Register (0x0F)
        4. 6.14.1.4 Test Registers
          1. 6.14.1.4.1 Test Register (0x1A)
          2. 6.14.1.4.2 Test Register (0x1B)
        5. 6.14.1.5 FIFO Control Registers
          1. 6.14.1.5.1 FIFO Status Register (0x1C)
          2. 6.14.1.5.2 TX Length Byte1 Register (0x1D) and TX Length Byte2 Register (0x1E)
  7. 7Applications, Implementation, and Layout
    1. 7.1 TRF7962A Reader System Using SPI With SS Mode
      1. 7.1.1 General Application Considerations
      2. 7.1.2 Schematic
    2. 7.2 System Design
      1. 7.2.1 Layout Considerations
      2. 7.2.2 Impedance Matching TX_Out (Pin 5) to 50 Ω
      3. 7.2.3 Reader Antenna Design Guidelines
  8. 8Device and Documentation Support
    1. 8.1 Getting Started and Next Steps
    2. 8.2 Device Nomenclature
    3. 8.3 Tools and Software
    4. 8.4 Documentation Support
    5. 8.5 Support Resources
    6. 8.6 Trademarks
    7. 8.7 Electrostatic Discharge Caution
    8. 8.8 Export Control Notice
    9. 8.9 Glossary
  9. 9Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6.12.6 Serial Interface Communication (SPI)

When an SPI interface is used, I/O pins I/O_2, I/O_1, and I/O_0 must be hard-wired as specified in Table 6-6. On power up, the TRF7962A looks for the status of these pins; if they are not the same (not all high, or not all low), the reader enters into one of two possible SPI modes:

  • SPI with slave select

    • or

  • SPI without slave select

The choice of one of these modes over the other should be made based on the available GPIOs and the desired control of the system.

The serial communications work in the same manner as the parallel communications with respect to the FIFO, except for the following condition. On receiving an IRQ from the reader, the MCU reads the TRF7962A IRQ Status register to determine how to service the reader. After this, the MCU must to do a dummy read to clear the reader's IRQ Status register. The dummy read is required in SPI mode, because the reader's IRQ Status register needs an additional clock cycle to clear the register. This is not required in parallel mode, because the additional clock cycle is included in the Stop condition.

A procedure for a dummy read is as follows:

  1. Starting the dummy read
    1. When using slave select (SS): set SS bit low
    2. When not using SS: start condition is when SCLK is high
  2. Send address word to IRQ Status register (0x0C) with read and continuous address mode bits set to 1
  3. Read 1 byte (8 bits) from IRQ Status register (0x0C)
  4. Dummy read 1 byte from register 0Dh (collision position and interrupt mask)
  5. Stopping the dummy read
    1. When using slave select (SS): set SS bit high
    2. When not using SS: stop condition when SCLK is high
TRF7962A procedure_dummy_read_slos732.gifFigure 6-14 Procedure for Dummy Read
TRF7962A dummy_read_spi_with_ss_slos732.pngFigure 6-15 Dummy Read Using SPI With SS