Even better, the TC4427A can be independently powered from the main circuit and uses just two control inputs, IN A and IN B for motor control. The inputs can work on as little as 2.4V making the TC4427A compatible with TTL, CMOS and even low core voltage devices such as the Raspberry Pi.
The circuit as shown above uses two switches to apply the input signal to pins 2 and 4, however the inputs could be driven from a different circuit, or micro-controller. The only requirement is that the input voltage is greater than 2.4V which is interpreted as a high signal, and 0.8V or less for a low signal. The IC can also withstand a high reverse current of up to 500mA and does not need reverse diode protection.
With two inputs there are four combinations. When the input is low, (ground or 0V) and high (input greater than 2.4V). The following table lists all input conditions and shows the state of the motor, where 0 represents the low and 1 represents the high state.
Input A | Input B | Function |
0 | 0 | Stop |
0 | 1 | Forward |
1 | 0 | Reverse |
1 | 1 | Stop |
Datasheet
Circuit Exchange International | Return to Control Circuits | https://www.cxi1.co.uk |