TIDUEW7 May   2020

 

  1.    Description
  2.    Resources
  3.    Features
  4.    Applications
  5.    Design Images
  6. 1System Description
    1. 1.1 Key System Specifications
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Processor – i.MX 6ULL Applications Processor
      2. 2.2.2 i.MX 6ULL Memory Interfaces
        1. 2.2.2.1 DDR3L
        2. 2.2.2.2 Quad SPI NOR Flash
        3. 2.2.2.3 eMMC iNAND
        4. 2.2.2.4 SD Card Connector
      3. 2.2.3 USB to UART Converter
      4. 2.2.4 USB Ports
      5. 2.2.5 LCD Screen Connector
      6. 2.2.6 JTAG Header
      7. 2.2.7 USB2ANY Header
      8. 2.2.8 Functional Switches and Status LEDs
      9. 2.2.9 GPIO Expansion Connector
    3. 2.3 Highlighted Products
      1. 2.3.1 TPS6521815 - Power Management IC
      2. 2.3.2 DP83849I - Dual Ethernet PHY
      3. 2.3.3 INA3221 - Current Monitor
      4. 2.3.4 Reset Scheme
      5. 2.3.5 TPS2054B, TPS22964C - Auxiliary Load Switches
    4. 2.4 System Design Theory
      1. 2.4.1 Power Estimation
      2. 2.4.2 Power Sequencing
      3. 2.4.3 I2C Device Chain
      4. 2.4.4 Clock Scheme
      5. 2.4.5 BOOT Configuration
      6. 2.4.6 PCB Floor Planning
  8. 3Getting Started, Testing Setup, and Test Results
    1. 3.1 Getting Started with Hardware and Software
      1. 3.1.1 Hardware
        1. 3.1.1.1 On-board LED Information
      2. 3.1.2 Software
        1. 3.1.2.1 Booting of TIDA-050043
        2. 3.1.2.2 Example Linux Commands for Testing TIDA-050043
  9. 4Design Files
    1. 4.1 Schematics
    2. 4.2 Bill of Materials
    3. 4.3 CAD Files
    4. 4.4 Gerber Files
    5. 4.5 Assembly Drawings
  10. 5Software Files
  11. 6Related Documentation
    1. 6.1 Trademarks
    2. 6.2 Third-Party Products Disclaimer

2.3.3 INA3221 - Current Monitor

To measure the live current information, a current sense circuit is inserted in series with the power nets from the PMIC to the processor. The current sensing is done with the INA3221 device. There are two devices used to monitor all the TPS6521815 PMIC power rails. The wiring is shown in Figure 13. The address pin A0 of the INA3221 device needs to be terminated according to Table 3.

Figure 13. INA3221 Current Sensor Wiring From PMIC to ProcessorTIDA-050043 tida-050043-current-sense-tiduew7.gif
1. Both of the I2C lines, SDA and SCL, require a pull-up resistor. A resistance of 2.2-kΩ is used to pull-up these open-drain signals to 3.3V

Table 3. INA3221 I2C Slave Address Options

7-BIT BINARY ADDRESS 7-BIT HEX ADDRESS ADDR PIN TERMINATION
1000000b 0x40 GND
1000001b 0x41 VS
1000010b 0x42 SDA
1000011b 0x43 SCL