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• TI Thinks Resolved

# TPS92690: TPS92690 SEPIC Design Calculator tools

Part Number: TPS92690

Hi Team,

May I know TPS92690 has SEPIC Design Calculator tools?

• Hello Kuo,

There isn't a design calculator for the 690 SEPIC, but the TPS92691 is very similar and has a SEPIC design tool that would work for the 690. There is also a TI Design for a 691 SEPIC that has the equations as well (PMP15027) that would be useful.

Just note one minor difference between the xls and the PMP, the PMP inductor equation is for separate inductors and the xls is for a coupled inductor. The only real difference is a factor of 2 (coupled inductors require less inductance for the same operation).

Regards,

Clint

• In reply to Clinton Jensen:

Dear Clinton,

I have question about 691 compensation formula type1 and type2 have 8.75 * 10^3 constants.
May I know 8.75 * 10^3 mean what?

Thanks!
Kuo
• In reply to Kuo John:

Hello Kuo,

I am not completely sure, but I will try and find out for you.

Regards,

Clint

• In reply to Kuo John:

Hello Kuo,

The systems engineer that developed the datasheet will be back in the office later this week. I'm sure it is just simplification from a few other constants or something of that nature, but I will try and find out when he is back. Sorry for the delay.

Regards,

Clint

• In reply to Kuo John:

Hello Kuo,

I'm still not 100% clear (the answer I got is kind of vague) but it is just a simplification of constants. It was described to me as the gain of 14 multiplied by the gM of the error amp multiplied by the pole frequency that will ensure at least 45 degrees phase margin for stability. I hope that helps a little, he at least ensures me it is correct.

Regards,

Clint