TPS7A90: Parallel LDOs

Austin Do

Intellectual 2865 points

Part Number: TPS7A90
Other Parts Discussed in Thread: TPS7A94, TPS7A92, TPS7A91

Tool/software:

Hello team,

My customer wants to use 2 TPS7A90 by parallel.

However, there is no device for TPS7A90 in https://www.ti.com/tool/download/PARALLEL-LDO-CALC

So, I selected TPS7A94 which have similar thermal impedance.

Is there any method to calculate ballast resistor for TPS7A70 in below condition?

Best Regards,

Austin

6 months ago

0 Stephen Ziel 6 months ago

TI__Mastermind 36735 points

Hi Austin,

We can add the TPS7A90 (and TPS7A91 and TPS7A92) into the parallel LDO calculator. I will get back to you on the timeframe to getting this updated in 1-2 business days.

Thanks,

Stephen

0 Stephen Ziel 6 months ago in reply to Stephen Ziel

TI__Mastermind 36735 points

Hi Austin,

We need to run transistor simulations to obtain the error voltage value. We should have those and the software tool should be updated in 3 weeks. I'll get back to you when this is complete. Thanks for your patience.

Thanks,

Stephen

0 Austin Do 6 months ago in reply to Stephen Ziel

TI__Intellectual 2865 points

Hi Stephen,

I'm not sure 3 weeks could be acceptable for the customer. Let me double check.

Is there a way to calculate the ballast resistor in manual? We can also validate and verify the value with your tool after 3 weeks.

Best Regards,

Austin

0 Stephen Ziel 6 months ago in reply to Austin Do

TI__Mastermind 36735 points

Hi Austin,

We are trying to speed up the progress on this request. Please give me 3-4 business days to provide an update.

Thanks,

Stephen

0 Stephen Ziel 5 months ago in reply to Stephen Ziel

TI__Mastermind 36735 points

Hi Austin,

Our transistor simulations show that the maximum offset voltage is +/- 2mV across all conditions and tolerances. I'm updating the calculator and it will take a couple of days to publish onto the internet. Here are the answers for the updated calculator, for now. Please reply back and let me know what questions / comments you have.