Anyone have a recommendation for a benchtop current sense amplifier?
Sure, there are current sense breakout boards and whatnot. But what I’d like is a convenient device that I can use to instrument a circuit and then monitor its current with my oscilloscope or logic analyzer (Saleae with analog input) along with other signals in the circuit.
Ideal features might be:
- Banana jack inputs and outputs
- Selectable range / sensitivity / sense resistor
- Isolated measurement, so I can measure high-side or low-side currents without worrying too much about the common connection on my scope
- Selectable or automatic power source selection, between circuit-powered and externally-powered
I haven’t seen anything like this in a few targeted searches, and just wondering if someone has any suggestions I might have missed.
I mean what you are describing sounds like an exact match for oscilloscope current probes : https://www.digikey.com/en/articles/understanding-selecting-effectively-using-current-probes They are expensive, but convert AC and DC current to a voltage range reasonable for a scope and do so in an isolated manner. Bandwidth is basically as much as you are willing to pay for.
For current shunts there is the EEVblog uCurrent but it’s not isolated, just a very low burden voltage shunt and amplifier essentially> https://www.eevblog.com/projects/ucurrent/
I swear I remember seeing the uCurrent before and TBH that’s probably what unconsciously inspired most of my wishlist. Thanks for the reminder. Seems to be unavailable (out of stock) currently…and I kind of wish it had a greater range. I’m semi-inclined to make my own.
For my immediate purposes I just ordered a few INA169 breakouts which will work well enough.