Output Actuators and Drive Techniques by Prof. Bitar

System Level Block Diagram C onsidering the Processing Block to Output Actuator Interface Input Sensor(s) Processing Output Actuator(s)

What are the Possible Outputs? LCD Display (7-Segment, Dot-Matrix…) LED Display (7-Segment…) Discrete LED’s Alarms (Speaker, Piezo-Electric…) Computer Interface (USB, Serial, Parallel…) Wireless (Blue Tooth, WiFi, ZigBee…)

Possible Displays… Images from

Audible Devices… Note: Images from

Computer Interfaces… Note: Images from

Cheap Wireless Modules… Available at Note: Images from

Processor Block to Output Device Interfacing Concerns Voltage Level Concerns Load Current Requirements Protocols (for Computer Interfacing)

Example 1: LCD Display Specification Sheet (Often a BAD Choice for ECE2799) Note: Image from

Example 2: LCD Module Specification Sheet (A Better Choice for ECE2799) Note: Image from

Microcontroller Development Boards? (Definitely a Time Saver) Note: Images from

Basic Drive Techniques Consider a typical Red LED IFIF +VF-+VF- I F = 20mA V F = 2.1V What are some of the concerns here? How many LED’s are you trying to drive? Can the Processing Block handle this?

Possible Solution(s) Using a Transistor or MOSFET Driver Processing Block VCC Q1 RB R1 LED1 VDD LED1 T1 R1

Piezo Alarm Example External vs. Internal Drive External Drive means that a switching signal in the audible range of frequencies must be provided. Internal Drive means that the oscillating circuit is self-contained in the device.

Piezo Alarm Example Note: Image from