Guru Mulay

Guru Mulay

>> M.S. in Computer Science at CSU Computer Vision Lab
>> Interested in Machine Learning, Computer Vision, Robotics, Embedded Electronics, and many more...
>> guru5[-aT-]colostate.edu

Tiny High Power DC Motor Driver using POWER Relays and SMD MOSFETs

Introduction:

Circuit Components:

  • Relays: Two 10A /24VDC relays were used as 4 switches for direction control.
  • ULN2003A IC: It is a Darlington pair IC. The current required to drive the coils of the relays was fulfilled by this Darlington pair IC.
  • MOSFET (IRF460N): This power MOSFET is capable of handling a large quantity of continuous currents and also its RDS(ON) is few milliohms, hence selected. Heat sink was also provided for proper heat dissipation.
  • Diodes: These are 2 freewheeling diodes used whenever freewheeling was required by the motor.

Printed Circuit Board:

Complete design of this motor driver can be found in th repository links above. Here is the schematic of the PCB.


Schematic: relay-mosfet dc motor driver

Fig. 1: Schematic: Tiny relay-MOSFET DC motor driver


Schematic: relay-mosfet dc motor driver

Fig. 2: PCB: Tiny relay-MOSFET DC motor driver

Here are some of the initial prototypes that I tried:

Load testing setup: tiny relay-MOSFET motor driver Load testing setup: tiny relay-MOSFET motor driver
Fig. 3: Load testing setup: tiny relay-MOSFET motor driver

Load testing setup: tiny relay-MOSFET motor driver Load testing setup: tiny relay-MOSFET motor driver
Fig. 4: Load testing setup: tiny relay-MOSFET motor driver


Schematic: relay-mosfet dc motor driver

Fig. 5: On Load: Tiny relay-MOSFET DC motor driver

Load testing setup: tiny relay-MOSFET motor driver Load testing setup: tiny relay-MOSFET motor driver
Fig. 6: Load testing setup: tiny relay-MOSFET motor driver