TPS61020: Startup problem

PAN-M

Part Number: TPS61020

Dear all.

Our customer changes USB and the input of the battery.
The battery is 3 cells Alkaline battery.
When it changed this circuit, it may not start by the voltage of the battery.
Input voltage of TPS61020 and the relations of the output voltage are as follows.

O is no problem, but does not start in the part of the X.

Please teach me what kind of problem is thought about.

Regards,
PAN-M

over 6 years ago

0 Jasper Li over 6 years ago

TI__Mastermind 46905 points

Hi PAN-M
Could you measure the input, SW and VOUT waveform to show the issue? we need the waveform to understand what happen

0 PAN-M over 6 years ago in reply to Jasper Li

Mastermind 8375 points

I will request it from a customer.
When Vo=5V, Output Current falls from around 4.7V in figure 1.
May I think that this point start Down Mode from here?
Regards,
PAN-M

0 Jasper Li over 6 years ago in reply to PAN-M

TI__Mastermind 46905 points

Hi PAN-M
yes. your understand is correct.

0 PAN-M over 6 years ago in reply to Jasper Li

Mastermind 8375 points

Jasper

Our customer acquired the waveform.
TPS61020_WF.xlsx

Is this start up problem in slva387?

Regards,
PAN-M

0 Jasper Li over 6 years ago in reply to PAN-M

TI__Mastermind 46905 points

Hi PAN_M,

We will check this in the EVM. may I know the loading during your measurement?

0 Minqiu Xie over 6 years ago in reply to PAN-M

TI__Mastermind 21565 points

Hi PAN-M:
I have close another thread. You could reply here.
And same question as Jasper's, may I know the loading during your measurement?

0 PAN-M over 6 years ago in reply to Minqiu Xie

Mastermind 8375 points

Minqiu
Yes, OK.
I am asking our customer your question about the load current.
Regards,
PAN-M

0 Minqiu Xie over 6 years ago in reply to PAN-M

TI__Mastermind 21565 points

Hi Pan-M:
Is there anything updated?
As the Chinese new year is coming, the reply maybe delay.

0 PAN-M over 6 years ago in reply to Minqiu Xie

Mastermind 8375 points

Thank you for support, Minqiu-san.
They get measurement current value again because they did not leave a detailed current value.
I talk to our customer your (delay) message.
Regards,
PAN-M

0 Minqiu Xie over 6 years ago in reply to PAN-M

TI__Mastermind 21565 points

Hi Pan-M:
Since we have another channel to contact, I'll close this post at first. Thank you for your understanding.

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TPS61020: Startup problem