ISO1212: use in TPS2373's TPH/TPL/BT pin to isolate LED

Polly Chung1

Part Number: ISO1212
Other Parts Discussed in Thread: TPS2373, , ISO1211

Dear expert,

My customer uses our TPS2373 and TPL/TPH/BT pins LED indicator need to be isolated. But TPS2373 datasheet (P33) suggest them to use photos to isolate. Could you please help check if ISO121x is suitable for this application? If yes, could you help provide the reference circuit including the connection and Rthr and Rsense value. Very appreciate your help.

P.S Vc is 12V.

Regards,

Polly Chung

over 6 years ago

0 Lucas Schulte9 over 6 years ago

TI__Expert 6955 points

Polly,

I am consulting with another expert on the matter. In the mean time, I have some questions. Is Vdd 12 volts as well? What is the voltage for the secondary side?

Respectfully,
Lucas

0 Polly Chung1 over 6 years ago in reply to Lucas Schulte9

TI__Intellectual 2110 points

Dear Lucas,

Thanks for your reply.
VDD is POE input, so it will be 40-57V. And they has 5V in secondary side. Thank you.

Regards,
Polly Chung

0 Lucas Schulte9 over 6 years ago in reply to Polly Chung1

TI__Expert 6955 points

Polly,

Here is the schematic that would work to isolate the LEDs with the ISO1211. The ISO1212 would be similar but with 2 channels. Also be sure to choose the proper Rthr and Rsense for this application as per the datasheet.

-Lucas

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ISO1212: use in TPS2373's TPH/TPL/BT pin to isolate LED