H-bridge braking with L293(D)

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1

I discovered how much braking power a Solarbotics GM9 can have when you short the terminals. I need that stopping power to make a robot that is suspended from a wire, wound around a spool, powered by a GM9.

But I also need to be able to power the motor in either direction. My platform of choice is the Picaxe 28 project board with a L293D motor driver chip.

How do I tell the L293 to short the terminals of the motor? I tried
high 4 high 5 ' both inputs high
and
low 4 low 5  ' both inputs low
but my motor will not brake.

Must I use the enable/disable pin on the L293D as well? Or should I get rid of this chip and get one without the internal flyback diodes (L293 without D)? Is a relay in order to tie the terminals together outside the main circuit?

2

The spec sheet is available

The spec sheet is available here.

There are some modes that should allow braking, depending on how you have your motors connected. Check out Figure 5 under the Application Information section. You should be able to use 1/2 of the L293D to drive each motor forward, revers, or “fast stop”.