Low bias buffer - Vcc to output drops too much

[chico]

I made a design where I wanted to make a voltage buffer with a very low voltage offset (Vcc to output).
I looked up the types of voltage buffers and then got a rail-to-rail buffer with a low voltage bias, but it still has troubles giving an output close to Vcc.
Currently I would like to power the IC with 5V and get 5V out.
The chip im using now (LMX324ASD+)gives 4.95V out, which is acceptable but I would prefer <0.1V drop.
Is there a certain type of buffer that I can use to get around this? or do I have to make a fancy active circuit?

IC URL: **broken link removed**

 

[ronv]

Why do you need to buffer it. Why not hook your load straight to Vcc.

 

[Nigel Goodwin]

EXACTLY what are you trying to do?.

 

[chico]

I have an intensity control on something I made, which is controlled from 0-5V.
In my design I have a 5V reference (from a different board) which I put through a pot. I found if i didnt buffer the signal, my 5V intensity input would wander.
Now that I have a buffer I get 4.95V out which is bad, but the signal is steady across all of my working conditions which is good.

 

[crutschow]

What type of circuit is sensitive to the last .05V out of 5V? Can you really see that in the intensity (of whatever you are controlling)?

 

[chico]

What type of circuit is sensitive to the last .05V out of 5V? Can you really see that in the intensity (of whatever you are controlling)?

Its not a big deal, it drops my intensity by 1% from the maximum (5V being 100% intensity), so i can really only control 0-99%, but i cant figure out how to fix it thats the biggest issue.

 

[crutschow]

Add a resistor from the output to the +5V to help with the pull-up. Try 2k ohm to start.