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How to Read the Schematic
ET2008 Sistem Embedded
• Schematics are our map to designing, building, and troubleshooting circuits.
• Understanding how to read and follow schematics is an important skill
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Schematic Symbols
• Resistors
• Potentiometers and Variable Resistors
Two terminals Three terminals
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• Capacitors
• Inductors
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• Switches
single-pole/single-throw
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• Power Sources
• Batteries
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• Voltage Nodes
• Diodes
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• Schottky diodes are useful in voltage clamping applications and prevention of transistor saturation
– Less energy is wasted as heat-> efficient choice for applications sensitive to efficiency -> they are used in stand-alone photovoltaic systems in order to prevent batteries from discharging through the solar panels at night as well as in grid-connected systems containing multiple strings connected in parallel
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• Transistors
– Bipolar Junction Transistors (BJTs)
Collector
Base
Emitter
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• Metal Oxide Field-Effect Transistors (MOSFETs)
Source Drain
Gate
• Digital Logic Gates
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• Integrated Circuits
TTLs
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Op Amps
Inverting
Non-inverting
• Voltage Regulators
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• Miscellany
– Crystals and Resonators
• Headers and Connectors
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• Motors, Transformers, Speakers, and Relays
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PTC symbol is the generic symbol for a thermistor, a temperature-dependent resistor (notice the
international resistor symbol in there?)
Name Designators and Values
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Reading Schematics
• Nets, Nodes and Labels
– Junction and nodes
• Net Names
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Schematic Reading Tips
• Identify Blocks
• Recognize Voltage Nodes
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• Reference Component Datasheets
– If there’s something on a schematic that just doesn’t make sense, try finding a datasheet for the most important component.
