A motor driver! I'm sure you knew that already but that's what it is. I like this one because it's very easy to build and pretty flexible on what you can do with it.
When do I need to use it?
A motor driver is required in pretty much all walkers including all of my CW series walkers. You need to use it any time you need to supply more current to the motors because the circuit can't supply enough.
This is a VERY easy circuit to build! Each input can be from a bicore, microcore....
Or in place of the ---(M)--- symbol that I use in other schematics (not this one duh!). A good example would be my CW series walker schematics. Just find the (M) and take the two connections going to it and hook them to the inputs of the driver. Stack 'em upQ - When I hook my motor directly to the battery it has lots of power but when I hook it to the motor driver it doesn't and can't even move my walkers leg.
A - Each driver supplies 50mA and since they are already doubled up you have 100mA which in most cases is not enough. The answer, stack 'em. You can see in the image on the right that all you have to do is stick another ALS245 on top and solder it on. It's that easy. You can stack as many as you need but you shouldn't need more than 3 and 2 should be plenty.
Nope not yet, however it's so simple I can't see why you would need a PCB.