Tuesday's DC current sensing

The problem yesterday was a dead IR2175. Today it looks a little better!



Now the OC has sorted itself out, however I still have a large pulse width for no current.

For some reason, there is a large voltage (approx 0.4V) between V+ and Vs. If I short these pins I should get 50% duty cycle.



Finally - something is working properly.

Now I need to work out why I am getting such a large voltage across V+ and Vs.

I discoverd I forgot a link on the PCB - it is pretty much working now with the pulse width doing what it should in both current directions. The only problem is that there is still a small offset when the current is meant to be zero - see below.



It is also interesting that even with this circuit, there is a bit of a slope when going up to 5V. Maybe I can try experimenting with smaller pullups.