I tried the SN754410 over the weekend and it wouldn't drive the solenoids (Common 12V and using the SN754410 to give a low signal to each of the 4 solenoids). I measured around 20 ohms with a multimeter. But regardless running two at a time wasn't working with this chip. It powered the leds just fine(had leds connected to the output of the SN754410 so I could visualize that it was working).
But no go. I definitely got VERY hot.
777funk:
But no go. I definitely got VERY hot.
This is why I recommended using mosfets. However, a high-gain low-saturation medium-current BJT such as the ZTX851 would also be suitable for switching 0.55A.
I'm a fan of MOSFETS at this point!
Are these DC solenoids or AC? For AC you need Traic's.
DC I believe.
Edit the chip actually does work. The LEDs were not getting juice because I had a 1.5k resistor in series (12V) and the solenoids were taking all the power so they weren't lighting up. But the solenoids are working just fine.
The chip does get very hot though I should add.