Transistors

This guide offers simple guidelines to help you decide when to use BJTs versus FETs based on your circuit’s needs.

BJTs (Bipolar Junction Transistors)

Use When:

• You need linear amplification with a high current gain.
• Your circuit benefits from well-established biasing methods.
• Low-power switching is required (e.g., driving relays).

Key Points:

• BJTs are current-driven.
• They excel in applications where predictable performance is important.
• Best suited for lower-frequency, current-based amplification.

FETs (Field-Effect Transistors)

Use When:

• Fast switching and low power consumption are critical.
• High input impedance is needed, such as in voltage amplification or digital circuits.
• Your design involves high-frequency or low-noise applications.

Key Points:

• FETs are voltage-controlled.
• They offer high switching speeds and low conduction losses.
• Ideal for interfacing with digital logic due to minimal current draw.