LM3481 Selection of RSEN/RSL

Hidekazu Fujikawa

Intellectual 460 points

Other Parts Discussed in Thread: PMP

Hello,

Please tell me the optimal resister value of RSEN/RSL when I depend on the slope compensation.

・VIN = 24V

・VOUT = 150V

・IOUT_max = 200m - 300mA

・L = 220uH

It is difficult to determine the RSEN and RSL value because of the variation of VSENS is too large.

Please tell me the recommended value.

In addition, I'd like to know also about the value of CSEN.

Although PMP8956 close to our condition is arranged 1000pF, can I use the same value without worrying about ISEN?

Best Regards,

H.Fujikawa

over 10 years ago

0 Murray Roose over 10 years ago

TI__Prodigy 530 points

Fujikawa-san, I've looked over the char data for VSEN and you can narrow the range down somewhat. Depending on the temp of operation the range would be 150-175mV. Does that help with your calculation then for Rsen and Rsl? Using the same value of CSEN as in the PMP will be fine, 100pF will also be ok.
Thanks,
Murray.

0 Hidekazu Fujikawa over 10 years ago in reply to Murray Roose

Intellectual 460 points

Murray san,

Thank you very much for your prompt reply.
We try to calculate the RSEN/RSL with your suggestion.

Thank you.
Best Regards,
H.Fujikawa

Power management

Power management forum

LM3481 Selection of RSEN/RSL