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How to drive latching relais ?

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Kleinstein:
For a circuit I may need some 4 (possibly more) latching relays. For the 2 coil version driving is relatively simple with one sided drivers (e.g. ULN2003 or similar).

However some of the smaller relays are one coil only and here driving is more tricky. Are there special chips for this ?
A see mainly 2 options: 
a) 1 full bridge bridge with 2 control lines.
b) a single sink/source driver and a series capacitor (e.g. some 10-100 µF) and only 1 control.

So far my idea would be an OP with sufficient output current, e.g. an TS912 driving a 12 V 15 mA coil.
The idle power ( ~1 mA for 2 OPs) is still a little on the high side.

Evan.Cornell:
Quick search turned up this:
https://www.maximintegrated.com/en/design/technical-documents/app-notes/3/3288.html

poorchava:
I use a dual lowside mosfet drivers for this. By using a complementary driver such as tc4428 you can turn this relay effectively into a normal non latching one. Tc4427 required 2 control lines but reduces power consumption

Kleinstein:
2 nice solutions, I did not have on my list. The gate drive could also be used with a capacitor.

The maxim app. note has a nice idea to use single sided drivers and extra resistors. It need more current for a short time, but only a rather short time, so it should be OK in may case, especially as I have a ~20 V supply and could thus use relatively large resistors. 

Simon:
Why not use a relay that is easier to drive. I am sure there are ones that you pulse to turn on and pulse to turn off. If you have to drive reverse polarity into the same coil then yes a H-Bridge that also turns off.

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