Dept. Compute Engineering, Chiang Mai University
What’s wrong with this circuit?
A microcontroller usually supplies limited current (i.e. 25 mA).
This is ok for LEDs but not enough for high current loads like a motor
Using transistors as a switch
Using a transistor
Relay “Poles” and “Throws”
Driving load with a relay
Bridge: A bi
IC / Module
There are many ways to drive output devices
Transistors are good for low power applications
Relays are suitable for AC power applications or when
low loss and high current is needed
bridge is for bi
Choose the right tool for the job!