TPS25750EVM: problem to operate only in PD source >5V-20V

Hi Felix, 

Thank you for reaching out!

The TPS25750 is not recommended for new designs. The TPS25751 is a follow-on device that specifically addresses known issues with integrated BQ support. Please see the following FAQ for more information. 

Best Regards, 

Aya Khedr 

HI Aya,

This doesn't answer my question if the problem is on the TPS25750 and I won't find it on the TPS25751.

I want operation only in 5-20V source. I checked when I connect only a power supply on the USB type C connector that the TPS25750 prohibits the passage of this power supply from VBUS IN to the PPHV signal. I cannot prohibit this passage. Can you help me how to program through the application a PS source only >5-20V function.

Hi Felix, 

Is the device powered on in this scenario (i.e. is VIN3V3 available)? Or is the device being powered from VBUS only?

The TPS25750/1 supports booting from a dead-battery condition (when VIN3V3 is unavailable) by asserting Rd on the CC lines. 

Best Regards, 

Aya Khedr

HI Aya,

The device being powered from VBUS only, 

In a future product, I would like to use the TPS25751 with a 5-20V power source only. When I connect a power supply only to the USB Type-C connector and my product is not powered by any other means, I would like the TPS25751 to forbit this power supply from passing from the VBUS input to the PPHV signal. Can we forbit this?

If it is possible, Can you help me to do this test with the TPS25750EVM and programming via the application a PD source function only >5-20V.

Best Regards

Hi Felix, 

The TPS25751 is best suited for DRP and sink-only applications since the device will assert Rd on the CC lines during boot when powered from VBUS only. In a source-only application, typically the device would be powered prior to plugging in another device. If the device is unpowered during boot (i.e powered ina dead-battery condition), we recommend pairing with a Type-C protection device such as the TPD6S300A and shorting the dead-battery resistors to GND. 

Best Regards, 

Aya Khedr

Thank you for the information. Before I created my schematic with the TPS25751D for my product, I tested the different USB Type-C PD configurations I'll need in my product with the TPS25750EVM.

Test source only 5V-3A: OK
Test source 5V-3A and sink 5V to 20V-3A: OK
Test sink 5V to 20V-3A: OK
Test source 5V to 20V-3A: NOK
I tested several ways with and without a charger by shorting Vsys to PPHV. I can't get it to work in this configuration. Vbus goes to 5V and then periodically cuts out.

Can you confirm that I can use it according to the attached schematic as a 5V to 20V source only? Can I test it with my TPS25750EVM?

Hi Felix, 

1- Could you share the json file used to test 20V sourcing? Do you have PD logs of the observed behavior? 

2- The TPS25751 is not best suited for source-only applications. In order to support 20V contracts, the PD controller must also support, 5V, 9V, 15V according to the PD spec. How are you controlling the DCDC?

Best Regards, 

Aya Khedr

  "questionnaire": {
    "device": "TPS25750",
    "toolBuildVersion": "1.0.2",
    "answers": [
      null,
      1,
      3,
      0,
      0,
      3,
      1,
      0,
      1,
      1,
      null,
      0,
      0,
      0,
      0
    ],
    "vendorId": "0000",
    "productId": "0000",
    "version": "1.0.0.2"
  },
  "configuration": {
    "data": {
      "selected_ace": [
        {
          "register": 6,
          "data": [
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0
          ]
        },
        {
          "register": 22,
          "data": [
            10,
            48,
            48,
            77,
            0,
            0,
            0,
            0,
            0,
            0,
            3
          ]
        },
        {
          "register": 50,
          "data": [
            2,
            168,
            42,
            44,
            145,
            1,
            38,
            44,
            65,
            6,
            0,
            44,
            177,
            4,
            0,
            44,
            65,
            6,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0
          ]
        },
        {
          "register": 51,
          "data": [
            0,
            44,
            145,
            1,
            16,
            44,
            209,
            2,
            0,
            44,
            177,
            4,
            0,
            244,
            65,
            6,
            0,
            69,
            65,
            6,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0
          ]
        },
        {
          "register": 92,
          "data": [
            48,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            16,
            0,
            0,
            0,
            0,
            0,
            0,
            48,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            12,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0
          ]
        },
        {
          "register": 117,
          "data": [
            0,
            0,
            0,
            0
          ]
        }
      ]
    }
  }
}

HI Aya,

Here's my .json file with a 5V and 20V 3A source configuration. I set PD0_1=5V-3A and PD0_2=20V-3A because I used a fixed 20V power supply on PPHV. This doesn't work; the Vbus output is always 5V and periodically cuts out after about 0.5 seconds.

I also tried a 5V and 9V 3A source configuration. I set PD0_1=5V-3A and PD0_2=9V-3A because I used a fixed 9V power supply on PPHV. This doesn't work; the Vbus output is always 5V and periodically cuts out after about 0.5 seconds.

The TPS252750EVM demo board should work in its normal source and sink version with the BQ25731 battery charger. But I have the same error. Can you give me a .json file in this configuration so I can make it work?

According to your previous answer in option 2, the TPS25751 cannot operate as a 20V source if the voltage on PPHV cannot be driven with the successive voltages 5V, 9V, 15V and 20V?

if I finally want to drive a DC/DC for the PPHV channel by the GPIOs is it possible?

If so, can you confirm that it configures the GPIO as output and chooses the EVENT Name: SourcePDO1Contract according to table 5-2 of the SLVUCR8A document.

Hi Felix, 

It seems that you did not select the correct configuration in question 1. In order for the PD to write to BQ, the first block diagram should be selected. 

I will get back to you on the remaining questions tomorrow. 

Best Regards, 

Aya Khedr

HI Aya,

test No. 1:

Here's my .json file with a 5V and 20V 3A source configuration. I set PD0_1=5V-3A and PD0_2=20V-3A because I used a fixed 20V power supply on PPHV. This doesn't work; the Vbus output is always 5V and periodically cuts out after about 0.5 seconds.

test No. 2:

I also tried a 5V and 9V 3A source configuration. I set PD0_1=5V-3A and PD0_2=9V-3A because I used a fixed 9V power supply on PPHV. This doesn't work; the Vbus output is always 5V and periodically cuts out after about 0.5 seconds.

test No. 3:

The TPS252750EVM demo board should work in its normal source and sink version with the BQ25731 battery charger. But I have the same error.

Can you give me a .json file in this configuration so I can make it work?

here is my .json file in this configuration

{
  "questionnaire": {
    "device": "TPS25750",
    "toolBuildVersion": "1.0.2",
    "answers": [
      null,
      0,
      3,
      0,
      0,
      0,
      3,
      0,
      1,
      1,
      2,
      12,
      2.944,
      0,
      0
    ],
    "vendorId": "0000",
    "productId": "0000",
    "version": "1.0.0.2"
  },
  "configuration": {
    "data": {
      "selected_ace": [
        {
          "register": 6,
          "data": [
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0
          ]
        },
        {
          "register": 22,
          "data": [
            10,
            48,
            48,
            77,
            0,
            0,
            0,
            0,
            0,
            0,
            3
          ]
        },
        {
          "register": 50,
          "data": [
            4,
            168,
            42,
            44,
            145,
            1,
            38,
            44,
            209,
            2,
            0,
            44,
            177,
            4,
            0,
            44,
            65,
            6,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0
          ]
        },
        {
          "register": 51,
          "data": [
            1,
            44,
            145,
            1,
            16,
            44,
            209,
            2,
            0,
            44,
            177,
            4,
            0,
            244,
            65,
            6,
            0,
            69,
            65,
            6,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0
          ]
        },
        {
          "register": 92,
          "data": [
            48,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            16,
            0,
            0,
            0,
            0,
            0,
            0,
            48,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            12,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0,
            0
          ]
        },
        {
          "register": 117,
          "data": [
            0,
            0,
            0,
            0
          ]
        }
      ]
    }
  }
}

According to your previous answer in option 2, the TPS25751 cannot operate as a 20V source if the voltage on PPHV cannot be driven with the successive voltages 5V, 9V, 15V and 20V?

if I finally want to drive a DC/DC for the PPHV channel by the GPIOs is it possible with  input voltage :15 to 24VDC.

If so, can you confirm that it configures the GPIO as output and chooses the EVENT Name: SourcePDO1Contract according to table 5-2 of the SLVUCR8A document.

if I finally want to drive a DC/DC for the PPHV channel by the GPIOs is it possible or i2c with input voltage :15 to 24VDC.

otherwise, solution with DC/DC controlled with i2c with 15 to 24VDC input. my system does not have a battery.

Hi Felix,

I will try to replicate on my end on a EVM. Note that the TPS25750 is not recommended for new designs and has limited support. 

The GPIO event mentioned would be used to control the DCDC to provide the voltages needed.