TPS7A3501　question

Masazumi Ishii

Genius 3945 points

Other Parts Discussed in Thread: TPS7A3501

Hello

I have a question.

device:TPS7A3501
Please see datasheet P11.

8.2.2.5 Start-up time
Equation (3)
T_startup = 250,000 × CNR (s)

The calculation value is wrong with the actual, but why is it?

Details are attached documents.

Thank you。

TPS7A3501.pdf

over 9 years ago

0 Ryan Eslinger over 9 years ago

TI__Guru 55940 points

Hi Masazumi,

Could you share what Channel 3 and Channel 4 are monitoring in your scope shot?

Very Respectfully,

Ryan

0 Masazumi Ishii over 9 years ago in reply to Ryan Eslinger

Genius 3945 points

Hi　Ryan-san

3ch:other power device output 1.8V

4ch:other power device output 3.3V

Details, Attached documents.

thank you.

Microsoft PowerPoint - TPS7A3501.pdf

0 Ryan Eslinger over 9 years ago in reply to Masazumi Ishii

TI__Guru 55940 points

Masazumi-san,

Thank you for the additional information. Are you seeing this on multiple devices?

I will attempt to replicate your application in order to help debug.

Very Respectfully,
Ryan

0 Ryan Eslinger over 9 years ago in reply to Ryan Eslinger

TI__Guru 55940 points

Masazumi-san,

I replicated your application and found that my results line up with the equation and table in the datasheet. Could you verify that the time you are measuring is 90% of the set Vout? Is it possible that there is a leakage path that could be charging the NR cap?

Very Respectfully,
Ryan

Power management

Power management forum

TPS7A3501　question

Power management

Power management forum

TPS7A3501 question

TPS7A3501　question