Controlling a Latching Relay via One I/O Pin.

erco

I found this idea interesting, even if on another forum: http://www.picaxeforum.co.uk/showthread.php?29157-Can-the-14m2-directly-control-a-latching-relay-with-a-5V-20ma-coil

The idea is to control a single-coil latching relay (alternate coil polarity to toggle relay contacts) using just one microcontroller pin and a series electrolytic capacitor. Saves power and pins. Probably not for mission critical apps, but when you need that extra push over the cliff...

"These go to eleven."

Ttailspin

One pin for a single-coil latching relay... wait, what?...

That's pretty cool, Have you tried it yet?, it somehow needs to be combined into one of your single servo bots.


-Tommy

jmg

erco wrote: »

The idea is to control a single-coil latching relay (alternate coil polarity to toggle relay contacts) using just one microcontroller pin and a series electrolytic capacitor. Saves power and pins. Probably not for mission critical apps, but when you need that extra push over the cliff...

...Also not for the average somewhat wimpy MCU pin, tho there are some MCUs now that can drive >> 30mA for LED use.
Care is needed to check the Voh and Vol, & load lines, as simply finding 25mA or similar MAX rating, certainly does not mean that pin can feed 5V at 25mA into a Coil!!

MikeDYur

Makes you really appreciate the Parallax Forums, with the addition of member example graphics, interest is increased along with clarity of the subject.