TPS7A05: Shorter start-up sequence device recommendation based on TPS7A05

Songzhen Guo

Part Number: TPS7A05
Other Parts Discussed in Thread: TPS7A24, TPS7A20, TPS7B69, LP2985, TPS784, TPS784-Q1

Hi expert,

TPS7A05 was mass production on customer side. Now there is a new project need LDO. Here is the requirement, could you recommend a new device for us ?Thanks.

Input voltage range: < 8V

Output voltage: Fixed to 5V

Max output current: 100mA

Start-up sequence: Less than 800us

Package: Better for SOT23-5, other package is also fine (Better p2p of TPS7A05--SOT23-5 pacakage)

Feather: Cost sensitive

Best Regards

Songzhen Guo

over 3 years ago

0 Wilson Fwu over 3 years ago

TI__Expert 4320 points

Hi Songzhen Guo,

TPS7A24 - specifically TPS7A2450DBVR is in same SOT-23-5 Package as TPS7A05 and should work here.

regards,

Wilson

0 Songzhen Guo over 3 years ago in reply to Wilson Fwu

TI__Intellectual 2790 points

Hi Wilson,

Thanks for your feedback. I look into the datasheet, I didn't find the power up time for Vout. Vout need settle down time need less than 800us after Vin is power the LDO. This is a important feather for Vehicle sensor. Could you check it for me? Thanks.

Best Regards

Songzhen Guo

0 Wilson Fwu over 3 years ago in reply to Songzhen Guo

TI__Expert 4320 points

Hi Songzhen,

Since this is for vehicle sensor, does it need to be Q100 qualified?

regards,

Wilson

0 Songzhen Guo over 3 years ago in reply to Wilson Fwu

TI__Intellectual 2790 points

Hi Wilson,

Thanks for you feedback.

This customer is focus on commercial vehicle. It doesn't need AEC-100. But the temperature grade need meet -40~125C. Could you give us a recommendation? Thanks.

Best Regards

Songzhen Guo

0 Wilson Fwu over 3 years ago in reply to Songzhen Guo

TI__Expert 4320 points

Hi Songzhen,

If customer can instead have VIN < 6V then TPS7A20 would be able to work (750us start-up time). We have pre-production material available now for sampling and will be releasing soon for SOT-23 package.

TPS7B69 could work here as well - according to Figure 17 on datasheet, the start-up time appears to be < 400us - TPS7B6950DBVR

regards,

Wilson

0 Songzhen Guo over 3 years ago in reply to Wilson Fwu

TI__Intellectual 2790 points

Hi Wilson，

After check the datasheet of TPS7A20 and TPS7B69, TPS7A20 is not suit for this case, for the start-up time at the full operating temperature, the max start-up time is 1150us. This is a application for vehicle sensor, the start-up time need less than 800us for full temperature range. T

TPS7B69 is suit for this case, could you provide the start-up time for full temperature range? Thanks.

By the way, TPS7B69 is much expensive than TPS7A20. Do we have other device can meet this requirement? Thanks.

Best Regards

Songzhen Guo

0 Songzhen Guo over 3 years ago in reply to Songzhen Guo

TI__Intellectual 2790 points

Hi Wilson,

I find LP2985 can meet customer's requirement, the power up sequence can change though Bypass Pin. If BYPASS is connected to ground by 100pF capacitor. The turn-on time is less than 500us. But it bad for low noise. It also recommend 10nF in datasheet. Could you comment on that? Thanks.