Re: Power for Spartan 3

Be careful of the resistor values. We have used these parts and from my
memory the LDO has a different reference voltage and hence resistor ratio to
the switcher elements. Your 40mV could be resistor or reference tolerance
have you checked those?

John Adair
Enterpoint Ltd. - Home of Hollybush1. The PC104+ Spartan3 Development Board.
http://www.enterpoint.co.uk

"Peter Mendham" <petermendham@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
message news:e3v0va$brk$1@xxxxxxxxxxxxxxxxxxx
Dear all,

I hope this isn't OT but I was wondering if anyone has any experience
using the TPS75003 to power a Spartan 3? For my particular application
I'm having to swap round the output voltages produced by one of the buck
convertors and the LDO with respect to most of the app notes. The
potential dividers which give the reference feedback in the app notes come
out to give a voltage which is consistently about 40mV above spec for all
three outputs. I was wondering if anyone knew why? Or is it just a bit
of design headroom?

TIA

-- Peter


.

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