+ 500 millivolts

[LarryH]

Complete newbie here

Does anyone have a circuit for producing this type of voltage?

I have a 3.3 v source - can I use a voltage regulator to reduce it appropriately? If so, which one and how?

Thanks

 

[edeca]

It very much depends what you need it for. Does it need to be precise? If so how precise? How much current do you need from it?

Without knowing what your use is it is quite hard to provide advice.

 

[LarryH]

Thanks,

it needs to be regulated, using it for an analog reference voltage on an Arduino Uno

hope this helps

 

[edeca]

Is there a particular reason for 500mV? For ADC voltage references it is more common to use a voltage that divides nicely into the maximum size.

I have used these before: https://www.electro-tech-online.com/custompdfs/2012/12/21653b.pdf

I can find a few 1.225v references from Maxim with a quick search.

 

[dougy83]

According to the datasheet I have on hand, i.e. 8271D–AVR–05/11 (Table 29-16), the minimum reference voltage is 1V. There's an internal 1.1V reference in the ATMEGA that you could use, or perhaps a resistor divider.

 

[KeepItSimpleStupid]

200 mV references exist, so you may have to amplify it. No big deal though.