SLVAF24 April   2021 TPS65988

 

  1.   Trademarks
  2. 1Automatic RDO for Explicit Contracts in SINK Role
    1. 1.1 Autonegotiate Sink Register (0x37)
    2. 1.2 Automatic PDO Selection as a Sink
    3. 1.3 Autonegotiate PDO Selection Flow
    4. 1.4 Autonegotiate Behavior Examples
  3. 2Multi Port Source Policy Management
    1. 2.1 Multi Port Source Policy Management Flow
  4. 3Multiport Sink Policy Management
  5. 4Revision History

1.1 Autonegotiate Sink Register (0x37)

This register allows the configuration of the TPS6598x device's automatic RDO selection behavior. The details of this register can be found in the Host Interface Technical Reference Manual of TPS6598x devices [SLVUBH2B]. Below is the register definition as available in the Technical Reference Manual (TRM).

Note: Writing this register while a sink contract is in place will not cause an automatic renegotiation. Changes will take effect the next time a contract is negotiated. The ANeg command forces a re-evaluation of this register and a new Request message will be issued if appropriate.
Note: The PD controller negotiates the PD contracts per the settings in this register regardless of the SNK Policy mode. However, power switches configured as input waiting for SRDY will only be enabled in SNKAutomaticMode. The PD controller in SNKIntrusiveMode can still disable specific switches during contract changes as described in the TRM.
Table 1-1 0x37 Auto Negotiate Sink Register
AddressNameAccessLengthPower-Up Default
0x37Auto Negotiate SinkRead/Write240 (Initialized by Application Customization)
Table 1-2 0x37 Auto Negotiate Sink Register Bit Field Definitions
Bits Name Description
Bytes 17-20: Non-Battery PDO Parameters
31:22 Reserved Reserved.
21:20 PeakCurrent Peak Current (See PD Spec)
19:10 Reserved Reserved.
9:0 MaximumCurrent Maximum Current (10-mA steps)
Bytes 13-16: Battery PDO Parameters
31:22 MinimumVoltage Minimum Voltage (50-mV steps)
21:20 Reserved Reserved (Write 0)
19:10 MaximumVoltage Maximum Voltage (50-mV steps)
9:0 MaximumPower Maximum Power (250-mW steps)
Bytes 9-12: RDO Current Parameters
31:20 Reserved Reserved (Write 0)
19:10 MinOperatingCurrent Min Operating Current (10-mA steps)
9:0 OperatingCurrent Operating Current (10-mA steps)
Bytes 5-8: RDO Power Parameters
31:20 Reserved Reserved (Write 0).
19:10 MinOperatingPower Min Operating Power (250-mW steps)
9:0 OperatingPower Operating Power (250-mW steps)
Bytes 3-4: Auto Negotiate Minimum Sink Required Operating Power
15:10 Reserved Reserved (Write 0)
9:0 ANSinkMinRequiredPower Minimum operating power required by the Sink in 250mW per LSB. Typically, this field is set to the maximum power across the PDOs defined in the TX Sink Capabilities Register (0x33).
NOTE: If the TX Sink Capabilities Register includes Battery supply type PDO(s), then the maximum power of Battery PDOs should be considered even when Fixed supply and Variable supply PDOs of higher power are available.
Byte 2: Auto-negotiate control
7:1 Reserved Reserved (Write 0)
0 AutoComputeSinkMinPower Decides if FW should compute minimum Sink operating power based on Sink Capability PDOs programmed in the TX Sink Capability register
0b PD Controller uses the value stored in the ANSinkMinRequiredPower field as the minimum operating power required by the SInk.
1b PD Controller will automatically compute the minimum operating power required by the SInk based on the Sink PDOs stored in the TX Sink Capabilities Register (0x33) and store it in the ANSinkMinRequiredPower field. The ANSinkMInRequiredPower is updated during the negotiation of a new contract.
Byte 1: Auto-negotiate control and RDO flags
7 RDOGiveBackFlag RDO GiveBack Flag
6 RDONoUsbSuspFlag RDO NoUSBSusp Flag
5:4 OfferPriority Offer Priority when evaluating PDOs offered by source
00b Higher current priority
01b Higher voltage priority
10b Higher power priority
11b Reserved.
3 RDOUsbCommCapable Flag RDO USB Communications Capable Flag
2 AutoNgtSnkVariable Auto Negotiate using Variable PDO
1 AutoNgtSnkBattery Auto Negotiate using Battery PDO
0 AutoNgt Auto Negotiate Fixed PDO This bit must be set for AutoNgtSnkVariable/Battery.