TPS62876-Q1: Compensation resistor and capacitor value calculation for TPS62876

Gary Teng

Genius 5840 points

Part Number: TPS62876-Q1

Tool/software:

Hi Sir,

My cusotmer is designing TPS62856 for their 2 power application:

VIN = 3.3V / Vout = 0.635V / Iout = 6.85A

VIN = 3.3V / Vout = 0.94V / Iout = 7.543A

We use webench to calculate the Rcomp and Comp value, but customer has concern about the different result in Webench and Equation in datasheet.

1. Which one we have to follow? What's the different by using webench and equations?

2. Any excel tool for TPS62876 to calculate those compensation value in customer's design?

Thanks and regards,

Gary Teng

0 Excel Regidor 1 day ago

Hi Gary,

Thanks for reaching out to us.

Who is the customer and for what application?

Best regards,

Excel

0 Gary Teng 1 day ago in reply to Excel Regidor

Genius 5840 points

Hi Excel,

It's a cable customer and used it for OSFP 800G AEC application.

Regards,

Gary

0 Excel Regidor 1 day ago in reply to Gary Teng

Hello Gary,

I will let Chris respond to your queries as he is our expert in optical transceivers application.

Best regards,

Excel

0 Chris Glaser 1 day ago

Hi Gary,

Can you send their schematic for me to review? It is the fastest way to get to the best answer.

Rcomp and Ccomp depend strongly on the output capacitance used.

In optical modules, there is typically not a load transient spec, so the D/S process cannot be followed.

We have a spreadsheet here that makes the math easier: https://www.ti.com/tool/download/TPSM8287B-CALC I can fill it out for you, once I know their total Cout.

Thanks,

Chris

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