Simple Voltage Reference Project

[EpicIntelGamer]

So it looks like the lower voltage winding has potential!

Indeed it does.

Oh I guess I posted this in the wrong thread 

That was meant to go in my Homemade PSU V2 Thread lol

[PA4TIM]

No, they are not from headers ( those do not have the golden inner "springs" ) but from a pcb out of some medical instrument. But you can use the pins from a good IC socket too.

Every Vref is usefull to calibrate something as long as it's value is much better known as that somethings accuracy.
You can build something with 4 TL431 like I did, it makes 10V but without reference or calibration you will never know the value.

A reference itself had several things. It has a typical value. Most can en will deviade a few mV from that. They most times come in several grades. The more change it is close to typical, the more expensive. The LT1027 for instance is in a A,B and C grade. The A grade is very hard to find, most sell the C grade, LT only samples the B, the A is the best.
So that makes a TL431 ( or other simple reference) without calibration only usefull for a cheap 2,5 digit multimeter or AVO 8 or so.
A reference needs time to stabilize. The fist few hunderd hours they change the most
The change by temp, relative humidity etc, but that is in the tens/hundereds of uV region. Not important for a 3,5 digit 1% meter.

Most references do not like o be loaded direct by a meter, they need a buffer amp behind them.

I have 7,5 digit meters, calibrators and standards so I can adjust and monitor a Vref with some confidence. Problem is the climate change in my lab. This gives me a 100 uV uncertanty. I have a climate independed knowh source so with a lot of work and enough speed I can bring it down to less as 5 uV

[EpicIntelGamer]

Been a while since there was activity in my thread and I recently thought of something and figured I'd ask here.

Now that I have a pretty nice reference (It shows 5.009VDC on my most accurate 4.5Digit meter which was last calibrated in 2004), is there a way I can use it or perhaps another REF02 regulator to help make a reasonably accurate current source?

[ve7xen]

Been a while since there was activity in my thread and I recently thought of something and figured I'd ask here.

Now that I have a pretty nice reference (It shows 5.009VDC on my most accurate 4.5Digit meter which was last calibrated in 2004), is there a way I can use it or perhaps another REF02 regulator to help make a reasonably accurate current source?

There are many ways, of course. A low offset opamp and a circuit like one of these: http://www.maximintegrated.com/app-notes/index.mvp/id/3869 with a precision resistor will get you reasonable accuracy for a low current source (e.g. 1mA).