LM2576: Adjusting the output voltage of a fixed output LM2576-5 slightly with a 200 Ohm resistor on feedback line

user6460252

Part Number: LM2576

Hi!

I have a design for a buck converter using a fixed output LM2576T-5.0.

I am currently adjusting the output voltage just slightly up, by about 0.1V using a 200 Ohm resistor in the feedback line.
I am asking is it acceptable to adjust the output of this device from 5v to 5.1V?
Accuracy is not a big concern for this design.
I would rather not redo the PCB for the adjustable version, since I already have the parts for this design.

Thanks,
Timo

over 3 years ago

0 Harrison Overturf over 3 years ago

TI__Genius 10655 points

Hello Timo,

It is acceptable to adjust the output voltage of the 5V fixed output voltage part, however you will need to include a resistive divider if you wish to adjust the output voltage from 5V to 5.1V. Follow Figure 32 equations in the datasheet and substituting Vref for 5V, the corresponding resistor divider values can be obtained.

Please see the E2E post I have provided below for more info, thanks.

https://e2e.ti.com/support/power-management/f/196/t/917549

Regards,

Harrison Overturf

Power management

Power management forum

LM2576: Adjusting the output voltage of a fixed output LM2576-5 slightly with a 200 Ohm resistor on feedback line