LM27402: Can change output voltage with fixed resistor value at FB pin?

Nicky Lim

Genius 3195 points

Part Number: LM27402
Other Parts Discussed in Thread: LM10011

Hello,

Can change LM27402 output voltage when resistor(Rfb1, Rfb2) values on FB pin are fixed?

If can change, how can I change the output voltage?

Please check and let me know.

Regards,

Nicky

over 5 years ago

0 Mathew Jacob1 over 5 years ago

TI__Expert 5900 points

Nicky,
You can change it using another Rfb2 resistor in par

0 Mathew Jacob1 over 5 years ago

TI__Expert 5900 points

Nicky,

You can change it using another Rfb2 resistor in parallel and figure out a way to include this by using logic fets. Another option is using a part like LM10011 to inject or draw a current from the FB pin to change the voltage.
Regards,
Mathew

0 Nicky Lim over 5 years ago in reply to Mathew Jacob1

Genius 3195 points

Hi Mathew,

Is there any way to change LM27402 output voltage without adding components? like as PWM control or etc....?
Adding Rfb2 is the only way to change output voltage?

Regards,
Nicky

0 Mathew Jacob1 over 5 years ago in reply to Nicky Lim

TI__Expert 5900 points

PWM control via an RC filter fed to the FB pin would also work.

Regards,
Mathew

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LM27402: Can change output voltage with fixed resistor value at FB pin?