TPS65982: TPS65982 SSD detection

Satoshi Yone

Part Number: TPS65982

Hi, Team,

A customer is testing TPS65982. TPS65982 cannot detect “Samsung Portable SSD T3”(250GB／Non PD) on one side Type-C cable.. Could you answer below questions?

CC line voltage is 1.68V: TPS65982 can detect SSD
CC line voltage is 1.51V: TPS65982 cannot detect SSD

1. TPS65982 cannot detect 1.51V. Is our understanding correct? or Is there any concern for SSD?
2. Please let us know Rp tolerance of TPS65982.
3. Could you teach us TPS65982 spec of CC voltage?

Best Regards,
Satoshi Yone

over 7 years ago

0 Rahul Sharma16 over 7 years ago

TI__Expert 6430 points

Hi Satoshi,

1.51V is within the Type-C specification. How do you know that SSD wasn't detected? It didn't enumerate on the PC or there was no VBUS at all?

Answer to your questions:
1. TPS65982 should detect 1.51V as a connect.
2. We have a current source to implement Rp, please check the section 6.8 for the tolerances.
3. We strictly follow the Type-C specs and you can see the range of valid CC voltages in section 4.11.3 of Type-C spec (release 1.3)

Thanks,
Rahul

0 Satoshi Yone over 7 years ago in reply to Rahul Sharma16

TI__Expert 3600 points

Hi, Rahul,

Thanks for the reply. There is no 5V output and PC OS cannot detect the SSD

Could you check the attached file?

Best Regards,
Satoshi Yone

Samsung Portable SSD Waveform.xlsx

0 Rahul Sharma16 over 7 years ago in reply to Satoshi Yone

TI__Expert 6430 points

Hi Satoshi,

I looked at the ppt and it looks like there is a big cap on the one of the CC line which is causing this issue. Can you find and tery to get rid of this cap and retest?

Also in the failing condition can you momentarily short the VBUS to ground and share the waveform with me?

Thanks,
Rahul

0 Satoshi Yone over 7 years ago in reply to Rahul Sharma16

TI__Expert 3600 points

Hi, Rahul,

Thanks for your support. The customer agreed the CC have a big cap.

Just for confirmation, The SSD doesn't satisfy Type-C spec, right?

Best Regards,
Satoshi Yone

0 Rahul Sharma16 over 7 years ago in reply to Satoshi Yone

TI__Expert 6430 points

Hi Satoshi,

Having a big cap on one of the CC line will violate the Type-C/PD specification.

Thanks,
Rahul

0 Satoshi Yone over 7 years ago in reply to Rahul Sharma16

TI__Expert 3600 points

Hi, Rahul,

Thanks!

Best Regads,
Satoshi Yone

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TPS65982: TPS65982 SSD detection