TPS54395- Designing Industrial power supply.

1. TPS54395 uses hiccup mode OCP/UVP protection.  It restarts automatically

2. I estimate about 1.9 A input current required.

3.  The recommended output capacitance is between 22uF - 68uF.  I have not tested the TPS54395 with that much output capacitance.  I have used similar converters with up to 220 uF.  It may be possible.  It will depend on the type of capacitor and the ESR.

Thanks for answer.

1)I think then 2.5A SMPS will be a safe bet. Because next design will be for 3.3V and 5V

2) Once we make this power supply, I will try out capacitor storage and will let you know the result.

 Thanks and Regards.

Suyog Vyawahare

May I know how did you concluded to 1.9A?  I mean how much loss you took into account?

just a rough calculation based on 85% efficiency.  You may actually get slightly better, but I wanted a conservative estimate.

As per datasheet and estimated load I was considering 89% efficiency and 80% in worst case scenario. Thankyou for validating my calculations and helping a power supply noob like me :)  

Also, you may want to consider moving your hold up capacitor(s) to the input.  You get more energy storage at 12 V input (= 1/2 CV^2).  Also, your supply will still regulate as the input voltage falls. towards the UVLO.

I was reviewing my designs, I think holding cap will be over kill. Because SMPS already has large capacitors, and already there is mains fail logic in our circuit. So I think we have mitigated all power failure conditions. 

1. UVP, OCP will be taken care by TPS54395
2. Brownout will be taken care by SMSP cap
3. And mains failure by circuit logic.