SPRAD67B December   2022  – September 2024 AM2431 , AM2432 , AM2434 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 Introduction
    1. 1.1 Before Getting Started With the Custom Board Design
    2. 1.2 Processor Selection
      1. 1.2.1 Availability of Tightly Coupled Memory (TCM)
    3. 1.3 Technical Documentation
      1. 1.3.1 Updated EVM or SK Schematics With Design, Review, and CAD Notes Added
      2. 1.3.2 FAQs to Support Custom Board Design
    4. 1.4 Design Documentation
  5. 2 Block Diagram
    1. 2.1 Constructing the Block Diagram
    2. 2.2 Configuring the Boot Mode
    3. 2.3 Confirming PinMux (PinMux Configuration)
  6. 3 Power Supply
    1. 3.1 Power Supply Architecture
      1. 3.1.1 Integrated Power
      2. 3.1.2 Discrete Power
    2. 3.2 Power (Supply) Rails
      1. 3.2.1 Core Supply
      2. 3.2.2 Peripheral Power Supply
      3. 3.2.3 Dynamic Switching Dual-Voltage IO Supply LDO
      4. 3.2.4 Internal LDOs for IO Groups (Processor)
      5. 3.2.5 Dual-Voltage IOs (for Processor IO Groups)
      6. 3.2.6 VPP (eFuse ROM Programming) Supply
    3. 3.3 Determining Board Power Requirements
    4. 3.4 Power Supply Filters
    5. 3.5 Power Supply Decoupling and Bulk Capacitors
      1. 3.5.1 Note on PDN Target Impedance
    6. 3.6 Power Supply Sequencing
    7. 3.7 Supply Diagnostics
    8. 3.8 Power Supply Monitoring
  7. 4 Processor Clocking
    1. 4.1 Unused Clock Input
    2. 4.2 Processor External Clock Source
      1. 4.2.1 LVCMOS Digital Clock Source
      2. 4.2.2 Crystal Selection
    3. 4.3 Processor Clock Output
  8. 5 JTAG (Joint Test Action Group)
    1. 5.1 JTAG and Emulation
      1. 5.1.1 Configuration of JTAG and Emulation
        1. 5.1.1.1 AM64x
        2. 5.1.1.2 AM243x [ALV]
        3. 5.1.1.3 AM243x [ALX]
      2. 5.1.2 Implementation of JTAG and Emulation
      3. 5.1.3 Connection of JTAG Interface Signals
  9. 6 Configuration (Processor) and Initialization (Processor and Device)
    1. 6.1 Processor Reset
    2. 6.2 Latching of the Boot Mode Configuration
    3. 6.3 Resetting the Attached Devices
    4. 6.4 Watchdog Timer
  10. 7 Processor Peripherals
    1. 7.1 Selecting Peripherals Across Domains
    2. 7.2 Memory (DDRSS)
      1. 7.2.1 Processor DDR Subsystem and Device Register Configuration
      2. 7.2.2 Calibration Resistor Connection for DDRSS
      3. 7.2.3 Attached Memory Device ZQ and Reset_N Connection
    3. 7.3 Media and Data Storage Interfaces
    4. 7.4 Ethernet Interface
      1. 7.4.1 Common Platform Ethernet Switch 3-port Gigabit Ethernet (CPSW3G)
      2. 7.4.2 Programmable Real-Time Unit and Industrial Communication Subsystem - Gigabit (PRU_ICSSG)
    5. 7.5 Universal Serial Bus (USB) Subsystem
    6. 7.6 Peripheral Component Interconnect Express (PCIe) Subsystem
    7. 7.7 General Connectivity Peripherals
    8. 7.8 Analog-to-Digital Converter (ADC)
      1. 7.8.1 Change Summary of AM64x, AM243x SR2.0 ADC Errata
    9. 7.9 Connection of Processor Power Supply Pins, Unused Peripherals and IOs
      1. 7.9.1 External Interrupt (EXTINTn)
      2. 7.9.2 Reserved (RSVD) Pins
  11. 8 Interfacing of Processor IOs (LVCMOS or Open-Drain or Fail-Safe Type IO Buffers) and Simulations
    1. 8.1 AM64x
    2. 8.2 AM243x [ALV]
    3. 8.3 AM243x [ALX]
  12. 9 Processor Current Rating and Thermal Analysis
    1. 9.1 Power Estimation
    2. 9.2 Maximum Current Rating for Different Supply Rails
    3. 9.3 Power Modes
    4. 9.4 Thermal Design Guidelines
      1. 9.4.1 AM64x
      2. 9.4.2 AM243x [ALV]
      3. 9.4.3 AM243x [ALX]
      4. 9.4.4 VTM (Voltage Thermal Management Module)
  13. 10Schematics:- Design, Capture, Entry and Review
    1. 10.1 Selection of Components and Values
    2. 10.2 Schematic Design and Capture
    3. 10.3 Schematics Review
  14. 11Floor Planning, Layout, Routing Guidelines, Board Layers, and Simulation
    1. 11.1 Escape Routing for PCB Design
    2. 11.2 DDR Layout Guidelines
    3. 11.3 High-Speed Differential Signals Routing Guidance
    4. 11.4 Board Layer Count and Stack-up
      1. 11.4.1 Simulation Recommendations
    5. 11.5 Reference for Steps to be Followed for Running Memory Simulation
  15. 12Custom Board Assembly and Testing
    1. 12.1 Guidelines and Board Bring-up Tips
  16. 13Device Handling and Assembly
    1. 13.1 Soldering Recommendations
      1. 13.1.1 Additional References
  17. 14References
    1. 14.1 AM64x
    2. 14.2 AM243x
    3. 14.3 Common
  18. 15Terminology
  19. 16Revision History

3.2.1 Core Supply

For the AM64x family of processors, core supply VDD_CORE is specified to operate at 0.75V or 0.85V (specified operating ranges defined in the Recommended Operating Conditions (ROC) table).

For the AM243x family of processors, core supply VDD_CORE is specified to operate only at 0.85V (specified operating ranges defined in the ROC table).

VDDR_CORE is specified to operate only at 0.85V (specified operating ranges defined in the ROC table).

When VDD_CORE is configured to operate at 0.75V, it is recommended to ramp 0.75V prior to all 0.85V supplies. When VDD_CORE is configured to operate at 0.85V, VDD_CORE and VDDR_CORE are recommended to be ramped together (powered from the same source).

Peripheral core supplies VDDA_0P85_SERDES0, VDDA_0P85_SERDES0_C, and VDDA_0P85_USB0 are specified to operate only at 0.85V.

Peripheral core supplies VDD_MMC0 and VDD_DLL_MMC0 are specified to operate only at 0.85V when the MMC0 peripheral is used. It is recommended to connect VDD_MMC0 and VDD_DLL_MMC0 to the same power source as VDD_CORE when MMC0 peripheral is not used.

For more information, see the Recommended Operating Conditions section in the Specifications chapter of the device-specific data sheet.

Note:

AM64x supports 0.75V or 0.85V core voltage. The Operating Performance Point (OPP) is not tied to the core voltage. There is no change in performance between 0.75V or 0.85V core voltage. The 0.75V supply provides an option to optimize power and the 0.85V supply optimizes the number of power rails without change in performance.

Note:

Setting the core supply to 0.8V is not an allowed option.