V-I converters

[stzarov]

hi everybody..we are required to design a voltage to current converter which will give an output of 0-20mA for the input of 0-10 V.we also want it not change with different resistance,i.e we want the current not to change with changing load line..do you have any ideas ?

 

[Sebi]

AD694

 

[stzarov]

it seems quite challenging,we can only use opamps and/or bjt's,could u simplify that design a little bit ???

 

[Roff]

hi everybody..we are required to design a voltage to current converter which will give an output of 0-20mA for the input of 0-10 V.we also want it not change with different resistance,i.e we want the current not to change with changing load line..do you have any ideas ?

Do you mean 4-20ma output, which is a common scheme for transmitting analog data, and which is shown on the schematic Sebi posted?

 

[Sebi]

Why opamps and BJT-s if existiert all in one chip: AD694? The precise solution with discretes more complicated. The example is a crop from original datasheet and show the 4-20mA setup, but the chip can work also with 0-20mA output.
https://www.analog.com/UploadedFiles/Data_Sheets/390142776AD694_b.pdf

 

[laroche73]

V-I converter

look at the following design note for some ideas, stzarov

**broken link removed**

 

[stzarov]

thank you all guys,we could handle it with the data you supplied for us,thanks again !!!