TPS25750: BC1.2 support in TPS25750

Angu Chen

Part Number: TPS25750
Other Parts Discussed in Thread: USB-PD-CHG-EVM-01, BQ25790, BQ25792

Hello,

I have programmed USB PD CHG EVM 01 board with the 7.0.4 customisation GUI.

The USB C PD works as expected however,

USB BC1.2 charging support does not. No matter what kind of USB A charger I plug in with a USBA-USBC cable, the maximum current I can get is 500mA.

Angu

over 2 years ago

0 Raymond Lin over 2 years ago

TI__Mastermind 28586 points

Hi Angu,

You will need to manually write into register 0x29 Port Control to enable BC1.2 and Proprietary Legacy Charger detection. By default, the TPS25750 is set to 00b (Do not detect any legacy charger).

Bits 31:30 controls this setting and you will need to set it to 11b in order to enable charger detection.

Thanks and Regards,

Raymond Lin

0 Angu Chen over 2 years ago in reply to Raymond Lin

Prodigy 20 points

Hey Raymond, thanks for that.

Is there no way to set this via the GUI Binary file?

What happens to this register if the device enters a dead battery mode?

Cheers,

Angu

0 Raymond Lin over 2 years ago in reply to Angu Chen

TI__Mastermind 28586 points

Hi Angu,

Unfortunately that is the default setting for the GUI generated binary file, this would need to be reconfigured after the TPS25750 is configured through the EEPROM.

If booting up from dead battery state the TPS25750 will receive its configuration from the EEPROM, hence this setting will always revert back to 00b.

Thanks and Regards,

Raymond Lin

0 Angu Chen over 2 years ago in reply to Raymond Lin

Prodigy 20 points

Hey Raymond,

I have tried to write to this register using a USB-PD-CHG-EVM-01 board and an Aardvark total phase I2C host.

I am connected to the I2C slave lines for the TPS25750.

I can read the register fine.

However when I go to write the rigister such that bit 31,30 = 11b. Nothing seems to happen.

I know I am writing the to the correct place as I can change the last byte from a C9 to a C8.

reading register 0x0D which is the Device Capability Register, it looks like BC1.2 is not supported. Bit 6-5 is 00b

0 Raymond Lin over 2 years ago in reply to Angu Chen

TI__Mastermind 28586 points

Hi Angu,

Can you try and see if writing CB will have any effect?

Thanks and Regards,

Raymond Lin

0 Angu Chen over 2 years ago in reply to Raymond Lin

Prodigy 20 points

Hey Raymond,

Here is a screen shot

I can write the first byte but not to the byte we want to change.

0 Raymond Lin over 2 years ago in reply to Angu Chen

TI__Mastermind 28586 points

Hi Angu,

Can you try writing CB to where C8 currently is?

Thanks and Regards,
Raymond Lin

0 Angu Chen over 2 years ago in reply to Raymond Lin

Prodigy 20 points

Please see the first part of the screen shot. Did you want me to test it for BC1.2 capabilities after changing it?

I can write CB to C8 fine.

0 Raymond Lin over 2 years ago in reply to Angu Chen

TI__Mastermind 28586 points

Hi Angu,

Yes please try testing for BC1.2 capabilities after changing C8 to CB.

Thanks and Regards,

Raymond Lin

0 Angu Chen over 2 years ago in reply to Raymond Lin

Prodigy 20 points

Hey Raymond,

This does not seem to change any behaviour around BC1,2

0 Raymond Lin over 2 years ago in reply to Angu Chen

TI__Mastermind 28586 points

Hi Angu,

Can you provide the JSON file for your configuration?

Thanks and Regards,

Raymond Lin

0 Angu Chen over 2 years ago in reply to Raymond Lin

Prodigy 20 points

Hey Raymond,

How would I provide a JSON file of my configurations?

I use the TI customization GUI to generate a binary that I flash to the system.

I have attached the Binary file.

These are my configurations

1. Sink Only.

2. N/A

3. 60W

4. N/A

5. No USB

6. N/A

7. No

8. No

9. BQ25790 & BQ25792

10. 12.6V

11. 3A

12. 0.24A

13. 0.28A

0 Raymond Lin over 2 years ago in reply to Angu Chen

TI__Mastermind 28586 points

Hi Angu,

Testing out your configuration, let me get back you latest end of the week.

Thanks and Regards,
Raymond Lin

0 Raymond Lin over 2 years ago in reply to Angu Chen

TI__Mastermind 28586 points

Hi Angu,

Apologies for the delay in response.

When you're reading register 0x29 through Aardvark control center, can you adjust the number of data bytes from 4 to 5? It seems like the register read you did initially didn't capture the entire register data. The 04 at the beginning of the read represents the data length, not actual register data. Refer to the screenshot shown below from our technical reference manual (page 11) on how we do I2C write and read (grey highlight represents output data):

Thanks and Regards,
Raymond Lin

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

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TPS25750: BC1.2 support in TPS25750