0-20mV programabble power supply

[mutta]

0-20mv

hi everybody i am a student, i have to do 0-20mV power supply but i dont know how can i do? pls help me

{thanks}

 

[IanP]

0-20mv power

One option is to employ a digital potentiometer, use 5V voltage reference and reduce the digital potentiometer output from 0-5V to 0-20mV by 2-resistor voltage divider ..
Another option is to use a digital to analog converter and again reduce its output voltage form whatever it produces (0-5V, for example) to 0-20mV using 2-resitor voltage divider ..
In both cases, if required, you can use a rail-to-rail voltage buffer-follower to ensure that your 0-20mV voltage source behavies like a voltage source ie. it has very low output impedance ..

Regards,
IanP

 

[mutta]

0-20mv power supply

can you send me circiut schema pls really i dont know i am beginer

 

[IanP]

Cutting story short, this is what I meant ..

Regards,
IanP

 

[mutta]

thank you so much man, have a nice day

Added after 13 minutes:

so can i ask? this circuit is sensible computation? for example 1mV,2mV,3mV,4mv....20mV?

 

[IanP]

What do you mean by that:

this circuit is sensible computation? for example 1mV,2mV,3mV,4mv....20mV?

Regards,
IanP

 

[mutta]

can we do it with wheatstone bidge ?

 

[roykyn]

use a microcontroller and a dac.....u can controll voltage from 0 to 5 volts....
then use a resistor divider network to get 20mV at full 5V input....then use a voltage follower if u want.....