Electronic Systems

• Sensors are input devices.
• Transistors are used as either an electronic switch or a current amplifier.
• Buzzers are output devices.
• LDRs and thermistors are sensors.
• LEDs are output devices.
• Buzzers use an internal oscillator to produce sounds at different frequencies when a current flows through them. Usually used in alarms, warning systems and electronic kids toys.
• Thermistors are usually used for greenhouses and fridges.
• The start/end flowchart symbol is a curved edged rectangle.
• The input/output flowchart symbol is a slanted rectangle.
• The process flowchart symbol is a normal rectangle.
• The decision flowchart symbol is a diamond.