LECT 3 ELE

What is the fundamental function of a diode?

• To amplify voltage

• To generate heat

• To allow current to flow in only one direction

• To store electrical charge

When a diode is 'forward-biased,' which of the following is true?

• Positive voltage is applied to the cathode.

• Negative voltage is applied to the anode.

• Positive voltage is applied to the anode, and negative to the cathode.

• No voltage is applied at all.

If a silicon diode has 0V applied to it, what is the forward current (IF​)?

• It is very large.

• It increases rapidly.

• It is zero (the diode is off).

• It causes the diode to overheat.

For a silicon diode, at what approximate forward voltage does the current begin to rise sharply (the 'knee' of the curve)?

• 0 V

• 0.3 V

• 0.7 V

• 5 V

Above the 0.7V 'barrier potential' for a silicon diode, if you increase the voltage slightly, what happens to the current?

• It stops flowing completely.

• It increases rapidly.

• It stays constant.

• It decreases slowly.

What causes the voltage across a forward-biased diode to increase only slightly above 0.7V, even when current rises sharply?

• The external power supply is running out of voltage.

• The diode's internal dynamic resistance.

• The diode getting too cold.

• A short circuit.

What does 'dynamic resistance (rd′​)' mean for a diode?

• Its resistance is fixed and unchanging, like a regular resistor.

• Its resistance increases as current decreases.

• Its resistance changes depending on the current flowing through it.

• It has no resistance at all.

When a diode is 'reverse-biased' but the voltage is below the breakdown voltage (VBR​), what kind of current flows?

• A large forward current.

• Absolutely no current.

• A small, tiny leakage current.

• A current that increases rapidly.

What happens to the reverse current when the reverse voltage reaches the breakdown voltage (VBR​)?

• It completely stops flowing.

• It suddenly increases rapidly.

• It flows in the forward direction.

• The diode automatically turns off.

What is the term for a special type of diode designed to safely operate in the reverse breakdown region?

• An LED

• A Rectifier diode

• A Zener diode

• A Transistor