Transistors

Definition

A transistor is a semiconductor device that regulates current or voltage flow. It acts as an amplifier and a switch, and is the fundamental building block of modern electronic devices and circuits, including those used in Ohm's Law.

5 Must Know Facts For Your Next Test

1. Transistors are made from semiconductor materials, typically silicon or germanium, and can be used as either amplifiers or switches in electronic circuits.
2. The three main types of transistors are bipolar junction transistors (BJTs), field-effect transistors (FETs), and metal-oxide-semiconductor field-effect transistors (MOSFETs).
3. Transistors are essential for the operation of Ohm's Law, as they allow for the control and manipulation of voltage, current, and resistance in electronic circuits.
4. The invention of the transistor in 1947 by John Bardeen, Walter Brattain, and William Shockley is considered one of the most important technological breakthroughs of the 20th century.
5. The miniaturization and integration of transistors on a single semiconductor chip has enabled the development of modern microprocessors, memory, and other digital electronic devices.

Review Questions

• Explain how transistors are used as amplifiers in electronic circuits.
  • Transistors can be used as amplifiers by controlling the flow of current between their three terminals: the source, gate, and drain. By applying a small signal to the gate terminal, the transistor can modulate a much larger current flowing between the source and drain. This allows the transistor to take a small input signal and produce a larger output signal, effectively amplifying the original signal. This amplification capability is crucial for various electronic applications, such as audio systems, radio transmitters, and signal processing circuits.
• Describe how transistors function as switches in digital electronic devices.
  • Transistors can be used as switches in digital electronic circuits, where they are responsible for turning on and off the flow of current. In this configuration, the transistor is operated in either a fully conductive (on) state or a non-conductive (off) state, allowing it to act as a binary switch. By using transistors as switches, digital devices can perform logical operations and store information in the form of binary data (0s and 1s). This switching capability is fundamental to the operation of microprocessors, memory chips, and other digital components that are essential for the functioning of Ohm's Law-based circuits.
• Analyze the importance of transistors in the development of modern electronic devices and their impact on Ohm's Law-based circuits.
  • The invention and subsequent miniaturization of transistors have been pivotal in the evolution of modern electronic devices and circuits. Transistors have enabled the creation of integrated circuits, where millions or billions of these semiconductor devices can be packed onto a single chip. This high level of integration has led to the development of powerful microprocessors, memory chips, and other digital components that are essential for the functioning of Ohm's Law-based circuits. The ability of transistors to control the flow of current and voltage makes them crucial for the implementation of Ohm's Law, which governs the relationships between current, voltage, and resistance in electronic circuits. Without the transistor, the modern electronic devices and systems that we rely on today would not be possible.

Related terms

Semiconductor: A material that has electrical conductivity between that of a conductor and an insulator, and whose conductivity can be modified by the addition of impurities or the application of electrical fields.

Amplifier: An electronic device that increases the magnitude of a signal, such as voltage, current, or power, without altering its essential features.

Switch: An electrical component that can break or complete an electrical circuit, turning power on or off.