The correct answer is:
ICEO = 1 + Ã
where:
- ICEO is the collector current with emitter open
- ICBO is the collector current with base open
- Ã is the current gain of the transistor
The current gain of a transistor is a measure of how much current the collector can draw for a given amount of current flowing into the base. A transistor with a high current gain can amplify a small signal into a larger signal.
When the base is open, no current flows into the base. This means that the only current flowing into the transistor is the current that flows through the emitter. This current is then amplified by the transistor and flows out of the collector.
The current gain of a transistor is typically specified at a specific collector current. For example, a transistor might have a current gain of 100 at a collector current of 1 mA. This means that for every 1 mA of current that flows into the base, the transistor will amplify the current and cause 100 mA of current to flow out of the collector.
The current gain of a transistor is not a constant value. It can vary depending on the operating conditions of the transistor, such as the collector current, the base current, and the temperature.
The current gain of a transistor is an important factor in determining the performance of the transistor. A transistor with a high current gain can amplify a small signal into a larger signal. This makes transistors useful for a variety of applications, such as amplifiers, oscillators, and switches.