TPS61040: VIN&EN fast power on make the startup fail

Garrick Dai

Part Number: TPS61040

Dears,

As below circuit, my customer found when VCC power on quickly(like about <3ms), the TPS61040 cannot startup. If slower down the VCC power up, the TPS61040 become normal. So what is reason for that and how to solve the issue? Thanks.

over 6 years ago

0 Jing Ji over 6 years ago

TI__Intellectual 2645 points

Hi Garrick,
I will test in the EVM and reply you later

0 Jing Ji over 6 years ago

TI__Intellectual 2645 points

Hi Garrick,
I have tested in the EVM and no this issue.
test conditon:
VIn=3V Vout=18V openload or 20mA; Vin increase slowly(1s) or quickly(500us )
I think this issue is because customer application.
Could you test some waveforms for me?
Vin; SW; VGH; FB
If you could test inductor current, it will be better.

0 Garrick Dai over 6 years ago in reply to Jing Ji

TI__Intellectual 1660 points

Hi Jing Ji,

It has no issue to test without load. But customer's load is actual LCD screen. So could you please add some capacitance to simulate the load? like several uF to hundreds of uF?

0 Jing Ji over 6 years ago in reply to Garrick Dai

TI__Intellectual 2645 points

Hi Garrick,
I will test in the EVM with a hundreds output cap and reply to you later.
I suggest you could test customer board and share some waveform with me, which will be helpful for us to solve this issue.

0 Garrick Dai over 6 years ago in reply to Jing Ji

TI__Intellectual 1660 points

Hi Jing Ji,

What's your email? I can send you customer test waveforms. and we can discuss more offline. Thanks.

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TPS61040: VIN&EN fast power on make the startup fail