Question

What is the function of Diode in a digital multimeter?

• A. To measure frequency
• B. To store electrical charge
• C. To control direction of flow of current
• D. To measure amount of AC voltage

Answer 1

The Correct Option is C

In a digital multimeter, a diode functions to regulate current direction. Diodes permit current flow in one direction (forward bias) and impede it in the reverse direction (reverse bias). This capability is vital for:

• Testing diodes and verifying their polarity.
• Safeguarding the meter against reverse polarity damage.
• Converting AC signals to DC within measurement circuits.

The diode test feature on a multimeter applies a minor voltage to the diode and records the voltage drop, typically ranging from 0.6V to 0.7V for silicon diodes under forward bias. Clarification of alternative functions:

• (A) Frequency measurement is handled by the frequency function, not the diode function.
• (B) Electrical charge storage is the primary role of a capacitor.
• (D) AC voltage measurement is performed by the AC voltage function.