Solid State Motor Control
Circuit : Andy Collinson
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This solid state motor control circuit uses the TC4427A MOSFET driver IC and is made by Microchip. Supply voltage can be from 4.5 to 18 Vdc and the IC has a peak output current of 1.5A

When you need to control a motor, there is always the problem of different supply voltage and current required by the motor. One solution is to use a dedicated driver IC. The TC4427A manufactured by Microchip, can operate on supply voltages from 4.5 to 18Vdc and supply a peak output current of 1.5A to the motor.

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.

Control Functions
Input AInput BFunction
TC4427 Pinout
The TC4427A is available as an 8 Pin DIP package and the pinout is shown below:

The datasheet can be downloaded from Microchips website, link below:

TC4427 Datasheet

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