L293D motor driver IC

Other Hardware Motors, Mechanics, Power and CNC
1

I have been trying to run a motor using l293d ic from the past week.

PIN 1,8,9,16 is connected to 5v dc supply
PIN 4,5,12,13 is grounded
PIN 3,6 is connected directly to a small DC motor

Here is the problem.........

Now, when the PIN 2 is connected to 5v, The motor should have been rotating in one direction. But this is not the case, The motor doesn't rotate at all. It only starts to rotate when the PIN 2(INPUT pin 1) is grounded.

May i please know why it is not working the way it should be ?

This problem still persists on different IC's.

2

Sounds like you have the 16 pin version, not the 20 pin.

Firstly you should be using a separate motor supply for pin Vs (pin 8), Arduino 5V is not safe
to share with a motor, you risk inductive spikes on the motor supply damaging the logic chips.

Secondly you are not connecting pin 7, which controls pin 6, so one side of the motor is not
in a defined state. pin 2 drives 3, 7 drives 6, so you should be setting 2 and 7 to opposite
logic states to make the motor turn.