LM51551: constant value

dongok lim

Part Number: LM51551
Other Parts Discussed in Thread: LM5176

hello.

I created the circuit (attachment 1) referring to the recommended circuit in the datasheet and verified the operation, but the problem is not outputting.
What should I check?

Since the circuit is attached, can you let me know if there is an unsuitable part for a constant, etc.?

over 5 years ago

0 Youhao Xi over 5 years ago

TI__Guru* 78060 points

Hi Dongok,

Thank you for using the LM51551. What is your input voltage? From the schematic is shows your Vout setting is at about 23.5V. If your input is higher than that, the circuit will see output over voltage and stop switching. This a boost circuit and the input is supposed to be lower than the output.

If you do want 22-36V in and 24V out, you should consider the LM5176 in a buck-boost converter.

Thanks,

Youhao Xi, Applications Engineering

0 dongok lim over 5 years ago in reply to Youhao Xi

Prodigy 70 points

Thank you very much, Youhao Xi.
The LM5176 chip you mentioned is too bulky, is there any way to do it with the LM51551?

I'm not a power design expert, so I don't know.
I designed it using the web provided by TI, and the parts have already purchased the LM51551.
Is there any best way to utilize current LM51551 parts?
The desired conditions are:
-Input: 22V ~ 36V
-Output: 24V / 3A