Hi,

I am working with an arduino to control a solenoid made by me, I understand that a diode across the coil will protect it from reverse flow of current, but in my scenario I am trying to switch the power using an H Bridge to reverse the polarity in this case I am not sure how to connect the diode correctly or is there any other was I can handle this problem?

Can someone give me idea on this?

Thanks in advance
-Prabhu

 

Obviously, you cannot put the diode across the coil. The diode is used to protect the semiconductor switches not the coil. Put it across these.

 

If you use a H-bridge with MOSFETs you generally don't need the diode. They already have an intrinsic body diode built in.

The voltage over the load is clamped to the power supply voltage of the H-bridge.

You can however add four diodes to your H-bridge, one on each MOSFET drain-source. (pointing to + of course)

An IGBT doesn't have a body diode, unless it is built in on purpose.

You would also need those diodes for an H-bridge with biploar transistors.

 

Generally a solenoid will work the same regardless of which way the current flows. Is this a type with a permanent magnet moving in it, like a voice coil?