TPS1685: TPS16851 FLTb and PG pin floating?

Hi Sir,

The TPS16851 will provide a power source and pass a 2-m long cable to the lighting tube devices.
Could you refer to the power-on waveform w/o TPS16851 and to review the TPS16851 calculated table? If the value needs to be adjusted, could you provide some comments? Thanks!

TPS16851 calculated table:TPS16851_CALC_20250523.xlsx

power-on waveform w/o TPS16851:

Hi,

Please let me check and get back.

Regards

Kunal Goel

Hi Sir,

Any update?

Hi Henry,

Values look fine.

Can you please label waveform?

Regards

Kunal Goel

Hi Sir,

Green line is the I-out, about 5.7A.

Yellow line is the V-out, about 49V.

The customer found the TPS16851 go to the latch status when the system power on, how to fix this issue? 

TPS16851 latch status waveform when the system power on:

TPS16851 schematics:

Hi Henry,

Please let me check and get back.

Regards

Kunal Goel

Hi Sir,

Any update?

Hi Henry,

You mean VOUT does not come up? 

Regards

Kunal Goel

Hi Sir,

Yes, the VOUT does not come up, and TPS16851 goes to the latch status.

For 50V/7A application, does the value in TPS16851 calculated table need to modify? 4011.TPS16851_CALC_20250523.xlsx

Let me check and get back soon.

Hi Sir,

Any update?

The customer also used the TPS1685EVM to perform the same test and obtained the same result. The VOUT does not come up(only 2V-out), and TPS16851 goes to the latch status.

Is there eload at evm output ?