Overview
This lecture introduces the basics of schematics in electronics, covering common symbols and conventions for representing electronic circuits.
What is a Schematic?
- A schematic is a diagram that represents the layout of an electronic circuit.
- Schematics use standardized symbols to illustrate the connections and components in a circuit, similar to a blueprint for a house.
Basic Schematic Symbols
- Straight lines in schematics represent wires connecting components.
- The DC power source (battery) symbol is a long line (positive) and a short line (negative).
- The AC power source symbol is a circle with a sine wave inside.
- A resistor is shown as a squiggly line, often labeled with its resistance value.
- An LED (Light Emitting Diode) is depicted as a triangle pointing to a line, with two arrows pointing away from it.
Key Details for Components
- The anode (positive side) of an LED is before the triangle; the cathode (negative/shorter leg) is after the line.
- Component symbols can include labels describing their value or name.
Wire Intersections and Connections
- Wires that cross with no dot at the intersection are not connected.
- Wires that cross with a dot at their intersection are connected and form an electrical node.
- Overlapping wires without a dot simply cross over each other for layout clarity.
Key Terms & Definitions
- Schematic — Diagram representing a circuit using symbols.
- DC Power Source — Symbolized by a long and short line; shows battery polarity.
- AC Power Source — Circle with a wavy line, representing alternating current.
- Resistor — Squiggly line, limits current flow.
- LED (Light Emitting Diode) — Triangle and line with outward arrows, emits light.
- Anode/Cathode — Anode is LED's positive side; cathode is negative side.
- Node — Point where two or more wires are connected (marked with a dot).
Action Items / Next Steps
- Review the basic schematic symbols discussed.
- Practice identifying symbols and understanding wire connections in simple circuit diagrams.
- Prepare for learning additional schematic symbols in upcoming lessons.