PWM output from a MCU to 4-20 mA current loop output

Hi all... :|

first of all pls apologize me for asking this question.. I know there are circuits available for this in google... But I am confused and badly in-need of help from you guys..... :---(

here is my problem :

I am looking for a Signal converter which converts 0-5 VDC PWM output from a MCU to 4-20 mA current loop output. I have selected the following ICs for the purpose :
XTR 115/116,
XTR 117,
XTR 110,
XTR 106.

The problem I am facing is the power which is used to excite the IC is not from the current loop. I have a separate regulator to do this. But I cannot find any options or pins to connect Vcc and Gnd. Please suggest me some IC which can fulfill our requirement.

Also, I am using this IC in developing a new product. So it should be available widely at-least for few years.

Guys pls suggest me some ways....
thanx in advance...:smile::smile:


-sathya

This will help:

**broken link removed**