How to simulate input into ADC

[pdovy]

proteus +trimpot simulate

I'm using a PIC that takes in a voltage between 0 and 0.4096 into its analog-digital-converter, and for testing purposes I need to be able to generate specific voltages in this range and feed them into the processor.

Is there any sort of variable power supply that I could use that would allow me to generate various voltages within this range?? I know I could buy a power supply of some sort, but I need some assurance of precision, more than what you get with turning a knob. Something that interfaces with the computer would be especially excellent.

Any ideas?

 

[Ace-X]

Just thought: take any precision DAC (like 16-bit MAX5200) connect it to the same uC (SPI port for MAX5200) and test your ADC.

 

[andy1]

If you're concerned about the accuracy of the ADC, then perhaps you want to calibrate and characterize before using. Please take a look at this Atmel appnote:

http://www.atmel.com/dyn/resources/prod_documents/doc2559.pdf

 

[glenjoy]

That type of voltage input is too low, first thinf first, how can you be ure of your reference to be too accurate also, and that kind of input range is too much affected by your supplies, so make sure you have a very stable power source or use a battery.

 

[muko]

use DAC of any supplier that suitable for PIC requirements

 

[puviarasu]

Hi
I have designed a simple ckt ot generate a mv source I have used it in my works it is very stable and cheep try it

for setting a particular voltage connect the ckt to the testing inputs adjust the pots(10k dual pot (stereo volume control) for corus adjustment and the multi turn trimpot(cheep than multi turn pot) with adapter for fine adjustment to get required voltage (measure the voltage using high impedance DMM) care must be taken to get accurate output as the ckt is purely resistive. Don’t set the output voltage and connect, as the load (your testing ckt’s impedance will change the output of the source(which is set).

bye
puvi

 

[dabi]

If you have proteus ,you can simulator it use software only , The proteus is great simulator for pic & avr & ms51!

 

[banh]

can we use digital potentiometer? (sth like we can change the resistance by changing a number)

 

[puviarasu]

we can use any potentiometer with a regulated referance voltage but it is very good practice to measure the voltage (output) using a precise DMM as the ADC input impedence( even though it is high) will alter the potentiometer resistances in turn changes the voltage(referance).
Regards,
Puvi