TPS55340: TPS55340 to achieve multiple rail outputs with SEPIC?

We only have Sepic EVM for single output. Could you please share the Vin, Vo1, Vo2...Io1, Io2...... with us so that we can have a study first?

Hi Helen,

This is for automotive application, the input is the car lead acid battery.

Vin range: +9V to +36V
Vout: +12V @ 2A x two rails.

Thanks a lot.

Best Regards,
Wei-Hao

For the Sepic converter, the voltage on the internal FET, the SW pin, is equal to the sum of the input voltage and the output voltage. As 36Vin +12Vo=48V>38V, so it is not fit to use TPS55340 in this applicaiton. Sugggest them use a boost controller in flyback topology. which will make the design more flexiable.

Suggest them use LM3478/81/88–Q1. There're some reference designs on these ICs. Or you can open a new post to ask for help.

Hi Helen,

Thanks for the reply, the maximum input is around +18V. They just need at least +36V rating device for the safety purposes.

My customer is interesting in is it viable to use SEPIC converter for multiple output rails?

Thanks.

Best Regards,
Wei-Hao