- Sat Jun 01, 2013 9:08 pm
#160091
Okay, Gonna make myself look stoooopid here, I'm sure. Just got the SN754410 H-bridge today, eagerly popped it into a breadboard to check it out. I built the most basic of circuits: 1,2EN are run to the +5V rail; Vcc1 (pin 16) goes to +5V rail; Vcc2 (pin 8 ) gets +3V. Pins 4,5,12,13 all go to Gnd. 1Y and 2Y run to the motor. According to the Data Sheet, if I send 1A or 2A high, the motor should turn (direction determined by which is taken high). Right????? Here's where I got lost....I ran 1A and 2A to momentary switches then onto the +5V rail. Powered the circuit up, pressed the 1A switch and got NOTHING. Pressed the 2A switch and got NOTHING. But wait, there's more... while fiddling, I ran the switch (from 1A) to Gnd, and viola, the motor began turning. So I ran the switch from 2A to the Gnd rail as well, and shock of all shocks... the motor turns one way when the 1A button is pressed, and the other way when the 2A button is pressed.... WTF??????? Any thoughts on what I've done here. I've managed the impossible, but I have no idea why!!