Re: trying to understand the REF pin on a DAC

On Mon, 29 Oct 2007 15:51:45 -0000, kasterborus@xxxxxxxxx wrote:

Can someone explain what the REF pin on my DAC is for?
It's an input voltage reference that can be GND, Vdd-1.5 or nominally
2.048v at Vdd =5v.

What is this voltage used for?
How does it affect the output?

Some of the circuits I see have tied this to Vdd - which seems too
high.

(The chip is the 5618 12-bit serial DAC)

Thanks,
Dave


The output voltage is

Vout = YourDigitalCode * Vref / 4096

so it directly affects the output.

John

.

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