LM25119: Output voltage problem

user5767499

Part Number: LM25119

Hi,

I have a problem with LM25119 chip. Output voltage is ~1V on each channel, assuming there should be 5V.

Vin is 24V. I measured VCC1 which is 7.5V. Voltage between VCC1 and HB is 6.47V, SS1 is 4.6V, FB1 is 0.8V, COMP1 is 1.08V., UVLO is 12V.

There are Cramp=1n, Rramp=28k,Rs=0.008Rm Rfb1=3.32 and Rfb2=17.8k mounted on the board. I used MOSFETS SiDR680DP.

Where should I look for a problem?

0 Qian Chen over 5 years ago

Hello,

Can you provide schematic in pdf file?

Also, please provide Vout and switch node waveform.

Thanks

Qian

0 user5767499 over 5 years ago in reply to Qian Chen

I resolved that problem. As far I've tested the board, everything works fine. Thanks.

0 Qian Chen over 5 years ago in reply to user5767499

Hi,

Thanks for the udpate. Good to know the issue was solved.

I'm going to close this post.

Thanks

Qian

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