TPS40422: TPS40422 TSNS1/2 BJT select

Tom Li53

Part Number: TPS40422

Hello,

My customer is designing TPS40422. Now they are asking about how to select the 2 BJT at TSNS1/2? Anything need to care when selecting this BJTs? Thanks!

over 6 years ago

0 Weidong Zhu over 6 years ago

TI__Expert 5965 points

Hi Tom,

The temperature sensing function is designed to work with 2N3904 series BJT, so please use xx3904 BJT in the design. Please also place a local decoupling cap near the BJT and IC (refer to datasheet). Thanks.

Regards,
Weidong

0 Tom Li53 over 6 years ago in reply to Weidong Zhu

TI__Prodigy 290 points

Hi Weidong,

Thanks for your support!

Can you share the principle of select the BJT? Customer want to use SOT-723 package due to the limit of space. While they can't find XX3904 with this package.

Tom Li

0 Weidong Zhu over 6 years ago in reply to Tom Li53

TI__Expert 5965 points

Hi Tom,

please refer to the below document for the temperature measurement. SOT-723 package should be ok as long as the layout is carefully taken care of.

Regards,
Weidong

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TPS40422: TPS40422 TSNS1/2 BJT select