TPS22965: Do we have rise time faster than 65us?

Paul Yeh

Genius 16515 points

Part Number: TPS22965
Other Parts Discussed in Thread: TPS22992

Hi team,

My customer had one project and used Intel Elkhart Lake platform.

And from specification define, the load switch output ramp up time should be less than 65us.

The power rail voltage is 1.05V (PVCCST_CPU).

According to our datasheet, it seems this chip can't meet this requirement, any suggestion?

Thanks

over 2 years ago

0 Kalin Burnside over 2 years ago

TI__Genius 13310 points

Hello Paul,

TPS22992 when biased with a 5V rail you could achieve rise times in the range you're looking for. You could tie the VBIAS to any other 5V rail in your system while providing the 1.05V to the input of the device.

This is also a very cost efficient solution.

Regards,

Kalin Burnside

0 Paul Yeh over 2 years ago in reply to Kalin Burnside

TI__Genius 16515 points

Kalin,

Thanks for your proposal but customer has one question if VBIAS=3.3V? how about Tr specification?

And what is Tr's formula if VBIAS=3.3V? Based on datasheet section9.3.3, it seems this formula is under VBIAS=5V condition.

Thanks

0 Kalin Burnside over 2 years ago in reply to Paul Yeh

TI__Genius 13310 points

Hello Paul,

With 3.3V Vbias the device will not meet the timing requirement you've listed as it does have an impact on slew rate control. Are they unable to bias the device with a 5V rail?

Regards,

Kalin Burnside

0 Paul Yeh over 2 years ago in reply to Kalin Burnside

TI__Genius 16515 points

Kalin,

After checking with customer, there is no %V Bias in system, they will only use 3V for VBIAS.

So they need to know how to calculate TR timing.

Please provide it.

Thanks

0 Kalin Burnside over 2 years ago in reply to Paul Yeh

TI__Genius 13310 points

Hello Paul,

TPS22992 will not meet your 65uS requirement with a 3.3V VBIAS. Its expected rise time would be ~107uS with CT = 0pF which is too slow for what you've indicated your customer needs.

What are the other requirements in terms of Ron, current, and features? TPS22992 was able to cover the same as 965; however, our faster rise time load switches have much lower ratings typically.

Load switch portfolio filtered by rise times

Regards,

Kalin Burnside

Power management

Power management forum

TPS22965: Do we have rise time faster than 65us?