# How to use a SN75441 h-bridge (not working as expected)

I am trying to figure out how to use an SN75441ONE h-bridge. I have it hooked up like this:

Pins 1, 8 and 16 are connected to the positive rail (+5 V). Pins 4, 5, 12 and 13 are connected to ground. Everything else is left alone. My expectation is that since all the input pins are LOW (here unconnected), the output pins should also be LOW. However, the output pins are all HIGH. What is going on here?

Your inputs are floating and not in a definite 'low' state. Using pulldown resistors around 1M$\Omega$ between the negative rail and the input pins will pull them low, while protecting $V_{cc}$ from ground when you input a high.