I need to control 5 motors independently from a microcontroller. At stall these motors only draw around .25A.
What is a circuit I can use for controlling 5 DC motors that draw about .25A max with as few pins as possible, under the condition that they will all be moving in the same direction at the same time (though possibly at different rates).
- use a full H-bridge for each one. 10 pins (base case)
- use one high-current half-H and 5 regular half-H, one side of motors all in parallel on the half-H. 6 pins
- use full-H for each motor, put one side of them in parallel. 6 pins
- use some magic IC (which I will find myself) where I can tie a digital direction input together for all chips. 6 pins
- use some IC that takes PWM signal and drives DC motor, 5 pins
Best Answer
simulate this circuit – Schematic created using CircuitLab
Figure 1. Where all motors only move the same direction one high current half-H-bridge can manage the motor common with individual half-bridges controlling the individual motors.
Number of switches required, \$ n = 2 + 2m \$ where \$ m \$ is the number of motors. For five fingers 12 control pins would be required. (With individual H-bridges 20 would be required.)