Finally i started selling the boards on Tindie! Take a look HERE
I take this opportunity to pubblish the results of the tests.
The tests measures voltage drop, voltage overshoot, rise time and temperature. Here you can see differents measures obtained with 2 different motors: a micromotors 12V 300mA geared motor and a lawnmower motor, running at 20V and absorbing 600mA with no load.
The tests is done at the worst condition, that is 50% of duty cycle and 1Khz of PWM frequency. Increasing the frequency will increases the efficency of the bridge. In particular, to use big motors i recommend to use a PWM frequency at least of 10-15Khz, for example by using the setPwmFrequency function on Arduino or by using another microcontroller (e.g. ARM or PIC)
Here you can see the different measures done on the output signal.MICROMOTORS MOTOR (temp: ~ 40°C)
Now i started designing the next version of the board (which includes better heat dissipation, power supply LED, and much more) and a shield adapter for Arduino, which enables you to use the A-BRIDGE with Arduino Boards