SLOS743M August   2011  – March 2020 TRF7970A

PRODUCTION DATA.  

  1. 1Device Overview
    1. 1.1 Features
    2. 1.2 Applications
    3. 1.3 Description
    4. 1.4 Functional Block Diagram
  2. 2Revision History
  3. 3Device Characteristics
    1. 3.1 Related Products
  4. 4Terminal Configuration and Functions
    1. 4.1 Pin Diagram
    2. 4.2 Signal Descriptions
      1. Table 4-1 Terminal Functions
  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  Overview
      1. 6.1.1 RFID and NFC Operation – Reader and Writer
      2. 6.1.2 NFC Device Operation – Initiator
      3. 6.1.3 NFC Device Operation – Target
        1. 6.1.3.1 Active Target
        2. 6.1.3.2 Passive Target
        3. 6.1.3.3 Card Emulation
    2. 6.2  System Block Diagram
    3. 6.3  Power Supplies
      1. 6.3.1 Supply Arrangements
      2. 6.3.2 Supply Regulator Settings
      3. 6.3.3 Power Modes
    4. 6.4  Receiver – Analog Section
      1. 6.4.1 Main and Auxiliary Receivers
      2. 6.4.2 Receiver Gain and Filter Stages
    5. 6.5  Receiver – Digital Section
      1. 6.5.1 Received Signal Strength Indicator (RSSI)
        1. 6.5.1.1 Internal RSSI – Main and Auxiliary Receivers
        2. 6.5.1.2 External RSSI
    6. 6.6  Oscillator Section
    7. 6.7  Transmitter – Analog Section
    8. 6.8  Transmitter – Digital Section
    9. 6.9  Transmitter – External Power Amplifier and Subcarrier Detector
    10. 6.10 TRF7970A IC Communication Interface
      1. 6.10.1 General Introduction
        1. 6.10.1.1 Continuous Address Mode
        2. 6.10.1.2 Noncontinuous Address Mode (Single Address Mode)
        3. 6.10.1.3 Direct Command Mode
        4. 6.10.1.4 FIFO Operation
      2. 6.10.2 Parallel Interface Mode
      3. 6.10.3 Reception of Air Interface Data
      4. 6.10.4 Data Transmission From MCU to TRF7970A
      5. 6.10.5 Serial Interface Communication (SPI)
        1. 6.10.5.1 Serial Interface Mode With Slave Select (SS)
      6. 6.10.6 Direct Mode
    11. 6.11 TRF7970A Initialization
    12. 6.12 Special Direct Mode for Improved MIFARE Compatibility
    13. 6.13 NFC Modes
      1. 6.13.1 Target
      2. 6.13.2 Initiator
    14. 6.14 Direct Commands from MCU to Reader
      1. 6.14.1 Command Codes
        1. 6.14.1.1  Idle (0x00)
        2. 6.14.1.2  Software Initialization (0x03)
        3. 6.14.1.3  Initial RF Collision Avoidance (0x04)
        4. 6.14.1.4  Response RF Collision Avoidance (0x05)
        5. 6.14.1.5  Response RF Collision Avoidance (0x06, n = 0)
        6. 6.14.1.6  Reset FIFO (0x0F)
        7. 6.14.1.7  Transmission With CRC (0x11)
        8. 6.14.1.8  Transmission Without CRC (0x10)
        9. 6.14.1.9  Delayed Transmission With CRC (0x13)
        10. 6.14.1.10 Delayed Transmission Without CRC (0x12)
        11. 6.14.1.11 Transmit Next Time Slot (0x14)
        12. 6.14.1.12 Block Receiver (0x16)
        13. 6.14.1.13 Enable Receiver (0x17)
        14. 6.14.1.14 Test Internal RF (RSSI at RX Input With TX ON) (0x18)
        15. 6.14.1.15 Test External RF (RSSI at RX Input with TX OFF) (0x19)
    15. 6.15 Register Description
      1. 6.15.1 Register Preset
      2. 6.15.2 Register Overview
      3. 6.15.3 Detailed Register Description
        1. 6.15.3.1 Main Configuration Registers
          1. 6.15.3.1.1 Chip Status Control Register (0x00)
          2. 6.15.3.1.2 ISO Control Register (0x01)
        2. 6.15.3.2 Control Registers – Sublevel Configuration Registers
          1. 6.15.3.2.1  ISO/IEC 14443 TX Options Register (0x02)
          2. 6.15.3.2.2  ISO/IEC 14443 High-Bit-Rate and Parity Options Register (0x03)
          3. 6.15.3.2.3  TX Timer High Byte Control Register (0x04)
          4. 6.15.3.2.4  TX Timer Low Byte Control Register (0x05)
          5. 6.15.3.2.5  TX Pulse Length Control Register (0x06)
          6. 6.15.3.2.6  RX No Response Wait Time Register (0x07)
          7. 6.15.3.2.7  RX Wait Time Register (0x08)
          8. 6.15.3.2.8  Modulator and SYS_CLK Control Register (0x09)
          9. 6.15.3.2.9  RX Special Setting Register (0x0A)
          10. 6.15.3.2.10 Regulator and I/O Control Register (0x0B)
        3. 6.15.3.3 Status Registers
          1. 6.15.3.3.1  IRQ Status Register (0x0C)
          2. 6.15.3.3.2  Interrupt Mask Register (0x0D) and Collision Position Register (0x0E)
          3. 6.15.3.3.3  RSSI Levels and Oscillator Status Register (0x0F)
          4. 6.15.3.3.4  Special Functions Register (0x10)
          5. 6.15.3.3.5  Special Functions Register (0x11)
          6. 6.15.3.3.6  Adjustable FIFO IRQ Levels Register (0x14)
          7. 6.15.3.3.7  NFC Low Field Level Register (0x16)
          8. 6.15.3.3.8  NFCID1 Number Register (0x17)
          9. 6.15.3.3.9  NFC Target Detection Level Register (0x18)
          10. 6.15.3.3.10 NFC Target Protocol Register (0x19)
        4. 6.15.3.4 Test Registers
          1. 6.15.3.4.1 Test Register (0x1A)
          2. 6.15.3.4.2 Test Register (0x1B)
        5. 6.15.3.5 FIFO Control Registers
          1. 6.15.3.5.1 FIFO Status Register (0x1C)
          2. 6.15.3.5.2 TX Length Byte1 Register (0x1D), TX Length Byte2 Register (0x1E)
  7. 7Applications, Implementation, and Layout
    1. 7.1 TRF7970A Reader System Using SPI With SS Mode
      1. 7.1.1 General Application Considerations
      2. 7.1.2 Schematic
    2. 7.2 Layout Considerations
    3. 7.3 Impedance Matching TX_Out (Pin 5) to 50 Ω
    4. 7.4 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 Glossary
  9. 9Mechanical, Packaging, and Orderable Information

Package Options

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

Supply Arrangements

Regulator Supply Input: VIN

The positive supply at VIN (pin 2) has an input voltage range of 2.7 V to 5.5 V. VIN provides the supply input sources for three internal regulators with the output voltages VDD_RF, VDD_A, and VDD_X. External bypass capacitors for supply noise filtering must be used (per reference schematics).

NOTE

VIN must be the highest voltage supplied to the TRF7970A.

RF Power Amplifier Regulator: VDD_RF

The VDD_RF (pin 3) regulator is supplying the RF power amplifier. The voltage regulator can be set for either 5-V or 3-V operation. External bypass capacitors for supply noise filtering must be used (per reference schematics). When configured for 5-V manual-operation, the VDD_RF output voltage can be set from 4.3 V to 5 V in 100-mV steps. In 3-V manual-operation, the output can be programmed from 2.7 V to 3.4 V in 100-mV steps. The maximum output current capability for 5-V operation is 150 mA and for 3-V operation is 100 mA.

Analog Supply Regulator: VDD_A

Regulator VDD_A (pin 1) supplies the analog circuits of the device. The output voltage setting depends on the input voltage and can be set for 5-V and 3-V operation. When configured for 5-V manual-operation, the output voltage is fixed at 3.4 V. External bypass capacitors for supply noise filtering must be used (per reference schematics). When configured for 3-V manual-operation, the VDD_A output can be set from 2.7 V to 3.4 V in 100-mV steps (see Table 6-2).

NOTE

The configuration of VDD_A and VDD_X regulators are not independent from each other. The VDD_X output current should not exceed 20 mA.

Digital Supply Regulator: VDD_X

The digital supply regulator VDD_X (pin 32) provides the power for the internal digital building blocks and can also be used to supply external electronics within the reader system. When configured for 3-V operation, the output voltage can be set from 2.7 to 3.4 V in 100-mV steps. External bypass capacitors for supply noise filtering must be used (per reference schematics).

NOTE

The configuration of the VDD_A and VDD_X regulators are not independent from each other. The VDD_X output current should not exceed 20 mA.

By default, the regulators are set in automatic regulator setting mode. In this mode, the regulators are automatically set every time the system is activated by setting EN input High or each time the automatic regulator setting bit, B7 in register 0x0B is set to a 1. The action is started on the 0 to 1 transition. This means that, if the user wants to rerun the automatic setting from a state in which the automatic setting bit is already high, the automatic setting bit (B7 in register 0x0B) should be changed: 1-0-1.

By default, the regulator setting algorithm sets the regulator outputs to a "Delta Voltage" of 400 mV below VIN, but not higher than 5 V for VDD_RF and 3.4 V for VDD_A and VDD_A.

Power Amplifier Supply: VDD_PA

The power amplifier of the TRF7970A is supplied through VDD_PA (pin 4). The positive supply pin for the RF power amplifier is externally connected to the regulator output VDD_RF (pin 3).

I/O Level Shifter Supply: VDD_I/O

The TRF7970A has a separate supply input VDD_I/O (pin 16) for the built-in I/O level shifter. The supported input voltage ranges from 1.8 V to VIN, not exceeding 5.5 V. Pin 16 is used to supply the I/O interface pins (I/O_0 to I/O_7), IRQ, SYS_CLK, and DATA_CLK pins of the reader. In typical applications, VDD_I/O is directly connected to VDD_X, while VDD_X also supplies the MCU. This ensures that the I/O signal levels of the MCU match the logic levels of the TRF7970A.

Negative Supply Connections: VSS, VSS_TX, VSS_RX, VSS_A, VSS_PA

The negative supply connections VSS_X of each functional block are all externally connected to GND.

The substrate connection is VSS (pin 10), the analog negative supply is VSS_A (pin 15), the logic negative supply is VSS_D (pin 29), the RF output stage negative supply is VSS_PA (pin 6), and the negative supply for the RF receiver VSS_RX (pin 7).