LM27762: feedback resistor

Alberto Doronzo

Part Number: LM27762

Hi ,

regarding the low side feedback resistor for the positive output (8.2.2.2 on the datasheet), the description says the resistor R2 should not be no less than 50kohm.

Is this because there is a risk of instability when the current is too high?

Or is it supposed to the the reverse and having too high of a low side resistor could increase susceptibility to noise?

Thank you much!

Regards,

Alberto

over 5 years ago

0 Febin over 5 years ago

TI__Mastermind 25430 points

Hi Alberto,

I am looking into this request. Meanwhile, do you have some schematic to explain what kind of application this device is used for.

Regards,

Febin

0 Alberto Doronzo over 5 years ago in reply to Febin

TI__Expert 4830 points

Hi Febin,

the potential application is to provide a slightly negative rail for op-amp supply to increase the headroom to ground.

No schematic at this point.

Best regards,

Alberto

0 Febin over 5 years ago in reply to Alberto Doronzo

TI__Mastermind 25430 points

Hi Alberto,

When R2 is lower obviously there's an increase in current in the feedback loop and you would not want this.

It is highly recommended to follow the datasheet specifications.

Regards,

Febin

0 Alberto Doronzo over 5 years ago in reply to Febin

TI__Expert 4830 points

Thanks for confirming Febin.

Best regards,

Alberto

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LM27762: feedback resistor