I'm working on a dc compressor inverter.
i'm trying to drive a small switched reluctance motor at around 1800 rpm using 3 tip120 darlingtons turned on/off in sequence.
I would like to isolate the power transistors from the ic by means of optocouplers, Wich one is the most convenient?
Darlingtons are the slowest switching devices you could have chosen, probably any opto coupler is OK as
it won't be much slower.
Use a low load impedance to get the best out of an opto coupler - a few hundred ohms.
If you need speedy switching you'll need MOSFETs and high-speed opto couplers. Electronics stockists provide
handy parametric search tools on their websites.
MarkT:
If you need speedy switching you'll need MOSFETs and high-speed opto couplers.
Translated: If you propose to use PWM for speed control.