SMPS design for Wide Vin AC supply range with Vout upto 5V, 10W design

Posted by: nikunj mehta on 01/24/2022

I have to design SMPS with below specification :-

Maximum AC input voltage        440     VAC

Minimum AC input Voltage 85       V

Switching Frequency 60-70    kHz

Efficiency 85-90%

Output Power (maximum)          10 W

Main Output voltage 5 V

AC Line frequency 50 Hz

Output ripple voltage                    0.15 - 0.25 V

i am planning to select 'Flyback converter' solution , please advise switcher IC with suitable solution as per above specification .

can you please guide me on design / guide on SMPS for Vin Wide range support ?

i was wonder if your technical team can help me to guide Transformer with 0.5 to 0.6 Max duty cycle and Wide range Vin (440-85VAC) support .

Can you please provide Spice Or LTSpice model of suggested switcher IC part ?

waiting for your positive feedback .

Comments

This design example should provide you with a start.

https://www.power.com/design-support/design-examples/der-889q-15-w-power-supply-800-v-bus-30-1200-vdc-input-using-innoswitch3-aq

I would also suggest that you download the latest version of PI Expert to aid with your design.

Thank you i will refer suggested link and inform you if i have any query

Hi Team,

I refer Calculation of the design and i have below query -

1) design calculation ok for lower range of Vin-85V , but for 500V it showing "TIME_ON_MIN" = 0.17uS Warning , as Vin increases our Ton time decreases and it will change our Duty cycle so this warning message can affect our Transformer design right ?.

2) as per Datasheet information for Higher Vin range it will support upto 20W , but as per my application i need 3-5W design only . as per application no load and 50% load waveform i hope there are no any issue with less Output power design , please give your suggestion on "TIME_ON_MIN" warning message .

Thank you

The VOR (reflected voltage) setting may be on the low side. Try changing to a higher VOR. This will result in a wider duty cycle due to a higher step-down ratio, but also higher drain voltage during off-time.