Voltage regulators

[Scarr]

Hi,
I have a project that needs 3 voltage regulators +5v 500ma, +3.8v 2amp +3.3v 200ma, currently I have them all supllied from the main +6v-+35v supply so all must accept a wide input voltage and all have smoothing caps (SMT tantalum, expensive!!) I was thinking about uprating the 5v regulator to 3amp and feeding the other two from the 5v reg.

I was hopeing to drop four caps as the supply to the other two regs should now be smooth and I can get lower spec 3.8v and 3.3v regulators as the input voltage is now only 5v

does this all sound OK? or will I hit problems?

The 5V is for logic and MCU etc. nothing powerfull hanging off it.

Thanks

Stephen Carr

 

[mozikluv]

regulator

hi,

check out **broken link removed** go to their power section and use their tool. they will provide you with what to use to suit your purpose.

"MERRY CHRISTMAS"

 

[Scarr]

Thanks for the link, but........

Can you see any problems with feeding two regs 3.3v 200ma + 3.8v 2amp fron a 5v 3amp regulator?

Just saves me a few expensive caps and maybe a little space and also I can use lower spec 3.3v+3.8v regs (no so wide an input range)

Thanks

 

[Nigel Goodwin]

Re: Thanks for the link, but........

Can you see any problems with feeding two regs 3.3v 200ma + 3.8v 2amp fron a 5v 3amp regulator?

No, it's common practice in commercial gear - but bear in mind you are pushing the 5V regulator fairly hard and will require good heatsinking.