SLVUCR8A September   2023  – March 2024 TPS25751

 

  1.   1
  2.   Read This First
    1.     Notational Conventions
    2.     Glossary
    3.     Related Documents
    4.     Support Resources
    5.     Trademarks
  3. 1Introduction
    1. 1.1 Introduction
      1. 1.1.1 Purpose and Scope
    2. 1.2 PD Controller Host Interface Description
      1. 1.2.1 Overview
      2. 1.2.2 Register and Field Notation
    3. 1.3 Unique Address Interface
      1. 1.3.1 Unique Address Interface Protocol
  4. 2PD Controller Policy Modes
    1. 2.1 Overview
    2. 2.2 Source Policy Mode
    3. 2.3 Sink Policy Mode
  5. 3TPS25751 Registers
  6. 44CC Task Detailed Descriptions
    1. 4.1 CPU Control Tasks
      1. 4.1.1 'Gaid' - Return to Normal Operation
      2. 4.1.2 'GAID' - Cold Reset Request
    2. 4.2 PD Message Tasks
      1. 4.2.1 'SWSk' - PD PR_Swap to Sink
      2. 4.2.2 'SWSr' - PD PR_Swap to Source
      3. 4.2.3 'SWDF' - PD DR_Swap to DFP
      4. 4.2.4 'SWUF' - PD DR_Swap to UFP
      5. 4.2.5 'GSkC' - PD Get Sink Capabilities
      6. 4.2.6 'GSrC' - PD Get Source Capabilities
      7. 4.2.7 'GPPI' - PD Get Port Partner Information
      8. 4.2.8 'SSrC' - PD Send Source Capabilities
      9. 4.2.9 'MBRd' - Message Buffer Read
    3. 4.3 Patch Bundle Update Tasks
      1. 4.3.1 'PBMs' - Start Patch Burst Mode Download Sequence
      2. 4.3.2 'PBMc' - Patch Burst Mode Download Complete
      3. 4.3.3 'PBMe' - End Patch Burst Mode Download Sequence
      4. 4.3.4 'GO2P' - Go to Patch Mode
    4. 4.4 System Tasks
      1. 4.4.1 'DBfg' - Clear Dead Battery Flag
      2. 4.4.2 'I2Cr' - I2C Read Transaction
      3. 4.4.3 'I2Cw' - I2C Write Transaction
  7. 5User Reference
    1. 5.1 PD Controller Application Customization
    2. 5.2 Loading a Patch Bundle
    3. 5.3 GPIO Events
    4. 5.4 AUTO_NEGOTIATE_SINK Register
      1. 5.4.1 AUTO_NEGOTIATE_SINK Usage Example 1
      2. 5.4.2 AUTO_NEGOTIATE_SINK Usage Example 2
      3. 5.4.3 AUTO_NEGOTIATE_SINK Usage Example 3
      4. 5.4.4 AUTO_NEGOTIATE_SINK Usage Example 4
  8. 6Revision History

5.4.2 AUTO_NEGOTIATE_SINK Usage Example 2

When attached to a 36W source the PD controller has RX_SOURCE_CAPS:

  • PDO1: 5V at 3A
  • PDO2: 9V at 3A
  • PDO3: 15V at 2.4A

The PD controller has TX_SINK_CAPS set as:

  • PDO1: 5V at 0.1A (fixed)
  • PDO2: 20V at 3A (fixed)

The PD controller has AUTO_NEGOTIATE_SINK set as:

  • AUTO_NEGOTIATE_SINK = 0
  • AUTO_NEGOTIATE_SINK.AutoComputeSinkMinPower = 1
  • AUTO_NEGOTIATE_SINK.AutoComputeSinkMinVoltage = 0
  • AUTO_NEGOTIATE_SINK.ANMinVoltage = 20V
  • AUTO_NEGOTIATE_SINK.AutoComputeSinkMaxVoltage = 1
  • AUTO_NEGOTIATE_SINK.NoCapabilityMismatch = x (see table below)
  • AUTO_NEGOTIATE_SINK.ANRDOPriority = 0

The settings give the results in the table below. Note that ANMaxVoltage computed as 20V, but it does not affect the result. Because the ANMinVoltage was set to 20V, and the source is not offering 20V none of the source PDOs fulfill the sink requirements. Even though ANSinkCapMismatchPower=0 in this example, because the voltages offered are insufficient, the capability mismatch bit can still be set.

Table 5-4 AUTO_NEGOTIATE_SINK Usage Example 2
AUTO_NEGOTIATE_SINK ACTIVE_CONTRACT_RDO
NoCapabilityMismatch OperatingX MinMaxOperatingX ObjectPosition Capability Mismatch
0 3.0A 3.0A 1 1
1 3.0A 3.0A 1 0