LMR14020

user4720089

Other Parts Discussed in Thread: LMR14020

I am using an LMR14020 to convert 28VDC to get 5VDC with a 1A current, using the schematic layout in the data sheet and component values from TI's WebBench software. I have put everything together in the circuit and checked to make sure nothing is shorted out, but my output voltage is about 1 volt less than my input voltage, regardless of how high or low I adjust my power supply. Any ideas as to what I am overlooking?

over 9 years ago

0 Luke Pan over 9 years ago

TI__Intellectual 2790 points

Hi,

Could you share the schematic? Also pls share the startup waveform just like the Fig23 in the datasheet.

Luke

0 user4720089 over 9 years ago in reply to Luke Pan

Prodigy 30 points

I don't have access to an o-scope to look at the waveform. I have a jpg of the schematic, but I am not seeing anything here that will allow me to post it.

0 user4720089 over 9 years ago

Prodigy 30 points

So fun fact: If you forget to connect the ground pin of the switcher to the circuit ground, it will not switch. Problem is solved and the circuit is putting out 5VDC.

Power management

Power management forum

LMR14020