i am successfully using an AD5412 in my design. The user can connect 3 wires:
- 24 V (industrial power supply)
- GND (ground from power supply)
- Output (4-20mA or 2-10V)
If the user connects the wires accidentally in a wrong way the AD5412 gets burned. I assume because of too high current for the interal clamping diodes.
So i added a reverse polarity schottky diode in series in each wire and everything is fine.
This solution has one disadvantage: The diode in the ground-path generates an unwanted offset voltage.
What is the recommended way to protect the chip for reverse polarity? Especially, how can i avoid to place a diode in the ground-path?
Thank you very much