I need to use a constant current source 20mA, the current flows through multiple diodes and resistors which are in series. The resistor value can vary from 0 to 1.6k and also a possibility of Open.
As the measuring device can read only upto 10V(Not multimeter, it is a 10V Analog Input Card), and at present 20mA*1.6k=32V+(diode drop). Hence I need to reduce this voltage before passing to the measuring device.
- Is there a simple way to do it?(Current Source is a must)
- To protect Open Condition of the resistor is a Zener Diode Sufficient?