Microcontroller Output Control
Arnan SipitakiatDept. 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
TransistorsUsing transistors as a switch
Using a transistor
Relay “Poles” and “Throws”
Driving load with a relay
Solid-State Relays
H-Bridge: A bi-directional driver
Transistor H-Bridge
H-Bridge IC / Module
ConclusionsThere are many ways to drive output devices Transistors are good for low power
applicationsRelays are suitable for AC power applications
or when low loss and high current is neededH-bridge is for bi-directional applicationsChoose the right tool for the job!