LM5164-Q1: LM5164-Q1

Roger Jefferies

Part Number: LM5164-Q1

Good morning.

We have a design for a +12 SM regulator, (nearly a copy of the reference circuit). This is working well for temperature but the output voltage is affected by the input voltage. The schematic is:

Pos 12V supply.pdf

The circuit is loaded with a 40R resistor. The output voltage is as follows and is at 22degC

Output voltages.pdf

Can you please tell me if this is expected, or is a problem

Regards

Roger Jefferies

11 months ago

0 Richard Fu22 11 months ago

TI__Genius 17680 points

Hi Roger,

This behavior looks normal. You may refer to curve 15 in section 8.2.3 of the datasheet, where it shows that for a fixed load, as the input voltage increases, the regulation target also increases as well.

Regards,

Richard

0 Roger Jefferies 11 months ago

Prodigy 60 points

Thanks Richard.

Is there s similar controller that has less Vo effect

Roger

0 Richard Fu22 11 months ago in reply to Roger Jefferies

TI__Genius 17680 points

Hi Roger,

No, this is dependent on your inductor and switching frequency selection. You may try a larger inductor to see lower ripple.

Regards,

Richard

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LM5164-Q1: LM5164-Q1