LMR64010: LMR64010 using externaly adjustable feedback voltage

John Tr

Part Number: LMR64010

Hello,

I am using basic application circuit for LMR64010 (https://www.ti.com/lit/ds/symlink/lmr64010.pdf?ts=1665993403256). Output voltage is adjustable by changing resistor R2 (R1 is fixed value 13.3KOhm). I would like to know how to modify this basic circuit to control the output voltage with an external voltage, instead of changing resistor R2. For this task I would like to use a 0-3.3V voltage signal (microcontroller PWM/DAC output).

over 3 years ago

+1 Lei Zhong over 3 years ago

TI__Mastermind 20120 points

Hi John,

Yes, the way you mentioned should work.

That is, with the feedback resistors(R1, R2) fixed, you can connect a suitable resistor to the DAC output, and then connect the resistor to FB pin. With so, the Vout can be adjusted by the DAC, which is controlled by the microcontroller.

Regards

Lei

0 John Tr over 3 years ago in reply to Lei Zhong

Prodigy 10 points

As I understand, I need to keep these resistors R1 and R2 connected as in basic circuit, but additionaly connect another resistor to FB node, that goes to mcu DAC?

0 Lei Zhong over 3 years ago in reply to John Tr

TI__Mastermind 20120 points

Hi John,

Yes, that's correct.

Regards

Lei

0 John Tr over 3 years ago in reply to Lei Zhong

Prodigy 10 points

Thanks a lot!

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LMR64010: LMR64010 using externaly adjustable feedback voltage