LM5161-Q1: LM5161-Q1 Fly-Buck spec review

Dexter,

The LM5161-Q1 will not be able to achieve this.

1. VIN must always be greater than VOUT. You cannot convert 9V to 12V with a buck (or the primary of a flybuck)
2. Current limit - The part is rated for 1A. That means 12V at 1A on the primary leaves no current for the secondary.
3. Flybucks have duty cycle limitations due to the leakage inductance of the transformer. The regulation of the secondary starts to become bad at high duty cycles (>50% for high Lleak). This wide input range requires a large duty cycle variation from VIN_MIN to VIN_MAX

For the specifications listed you may need a dual-stage solution. If the specs are flexible, which specs are flexible?

-Sam

Dear Sam,

Thank you for your reply.

Can you recommend the solution one of below specs.

1. Vin 9V~95V, Vout1-12V 2A (isolation), Vout2- 12V 1A(isolation), Vout3- 6V 1A(Isolation)

2. Vin 9V~95V, Vout1- 12V 2A (non-isolation), Vout2- 12V 1A (isolation)

Thanks.

Dexter,

For these specs I'd recommend a flyback. I will notify the flyback group to help you with your part selection. They should respond in a day or two.

Thank you,

-Sam