SPRUIS4E March   2022  – January 2024

 

  1.   1
  2.   Jacinto7 J721E/DRA829/TDA4VM Evaluation Module (EVM)
  3.   Trademarks
  4. 1Introduction
    1. 1.1 Key Features
    2. 1.2 Thermal Compliance
    3. 1.3 REACH Compliance
    4. 1.4 EMC, EMI, and ESD Compliance
  5. 2J721E EVM Overview
    1. 2.1 J721E EVM Board Identification
    2. 2.2 J721E SOM Component Identification
    3. 2.3 Jacinto7 Common Processor Components Identification
    4. 2.4 Quad Ethernet Components Identification
  6. 3EVM User Setup/Configuration
    1. 3.1 Power Requirements
    2. 3.2 Power ON Switch and Power LEDs
      1. 3.2.1 Over Voltage and Under Voltage Protection Circuit
      2. 3.2.2 Power Regulators and Power Status LEDs
    3. 3.3 EVM Reset/Interrupt Push Buttons
    4. 3.4 EVM DIP Switches
      1. 3.4.1 EVM Configuration DIP Switch
      2. 3.4.2 SOM Configuration DIP Switch
      3. 3.4.3 Boot Modes
      4. 3.4.4 Other Selection Switches
    5. 3.5 EVM UART/COM Port Mapping
    6. 3.6 JTAG Emulation
  7. 4J721E EVM Hardware Architecture
    1. 4.1  J721E EVM Hardware Top level Diagram
    2. 4.2  J721E EVM Interface Mapping
    3. 4.3  I2C Address Mapping
    4. 4.4  GPIO Mapping
    5. 4.5  Power Supply
      1. 4.5.1 Power Sequencing
      2. 4.5.2 Voltage Supervisor
      3. 4.5.3 DDR I/O Voltage Selection
        1. 4.5.3.1 J721E SoC S2R Logic Flow Diagram
        2. 4.5.3.2 J721E SoC MCU Only Operation
        3. 4.5.3.3 Power Monitoring
    6. 4.6  Reset
    7. 4.7  Clock
      1. 4.7.1 Processor’s Primary Clock
      2. 4.7.2 Processor’s Secondary/SERDES Ref Clock
      3. 4.7.3 EVM Peripheral Ref Clock
    8. 4.8  Memory Interfaces
      1. 4.8.1 LPDDR4 Interface
      2. 4.8.2 OSPI Interface
      3. 4.8.3 UFS Interface
      4. 4.8.4 MMC Interface
        1. 4.8.4.1 MMC0 - eMMC Interface
        2. 4.8.4.2 MMC1 – Micro SD Interface
      5. 4.8.5 Board ID EEPROM Interface
      6. 4.8.6 Boot EEPROM Interface
    9. 4.9  MCU Ethernet Interface
      1. 4.9.1 Gigabit Ethernet PHY Default Configuration
    10. 4.10 QSGMII Ethernet Interface
    11. 4.11 PCIe Interface
      1. 4.11.1 X1 Lane PCIe Interface
      2. 4.11.2 X2 Lane PCIe Interface
      3. 4.11.3 M.2 PCIe Interface
    12. 4.12 USB Interface
      1. 4.12.1 USB 3.1 Interface
      2. 4.12.2 USB 2.0 Interface
      3. 4.12.3 USB 3.0 Micro AB Interface (Reserved Port)
    13. 4.13 CAN Interface
    14. 4.14 FPD Interface (Audio Deserializer)
    15. 4.15 FPD Panel Interface (DSI Video Serializer)
    16. 4.16 Display Serial Interface (DSI) FPC
    17. 4.17 Audio Interface
    18. 4.18 Display Port Interface
    19. 4.19 MLB Interface
    20. 4.20 I3C Interface
    21. 4.21 ADC Interface
    22. 4.22 RTC Interface
    23. 4.23 Apple Authentication Header
    24. 4.24 EVM Expansion Connectors
    25. 4.25 ENET Expansion Connector
      1. 4.25.1 Power Requirements
      2. 4.25.2 Clock
        1. 4.25.2.1 Main Clock
        2. 4.25.2.2 Optional Clock
      3. 4.25.3 Reset Signals
      4. 4.25.4 Ethernet Interface
        1. 4.25.4.1 Quad Port SGMII PHY Default Configuration
      5. 4.25.5 Board ID EEPROM Interface
    26. 4.26 CSI Expansion Connector
  8. 5Revision History

4.5.3 DDR I/O Voltage Selection

There is a DIP switch provided on the J721E SoM to select the SoC’s DDR and LPDDR4 memory I/O supply for the LPDDR4/LPDDR4x.

Currently, the J721E device does not support LPDDR4x. This support may be added at a later date. The EVM does support this feature if/when support is added to the silicon.

The DIP switch SW1 Bit 1 provides an option to change the logic of D Flip-Flop (U7) that controls the Load Switches TPS22965TDSGRQ1 and TPS22976NDPUT to decide the I/O supply voltages.

Table 4-4 DDR I/O Voltage Selection
SW1 Bit 1 SDRAM_TYPE Selected DDR I/O Voltage
LOW LPDDR4X 0.6V
HIGH LPDDR4 1.1V
GUID-F3A79143-882C-4FE8-AA1E-BFEA258EEF5D-low.gif Figure 4-6 LPDDR4 IO Voltage Selection Circuit