What is the gain of a transistor?

What is the gain of a transistor?

The current gain for the common-base configuration is defined as the change in collector current divided by the change in emitter current when the base-to-collector voltage is constant. Typical common-base current gain in a well-designed bipolar transistor is very close to unity.

What is the gain of common-collector?

As you discovered in Lab 6, the common-collector amplifier has a voltage gain of about 1, or unity gain. The common-collector amplifier is considered a voltage-buffer since the voltage gain is unity.

How do I test a transistor?

Hook the positive lead from the multimeter to the to the BASE (B) of the transistor. Hook the negative meter lead to the EMITTER (E) of the transistor. For an good NPN transistor, the meter should show a voltage drop between 0.45V and 0.9V. If you are testing PNP transistor, you should see “OL” (Over Limit).

What is HFE for a transistor?

hFE is an abbreviation, and it stands for “Hybrid parameter forward current gain, common emitter”, and is a measure of the DC gain of a junction transistor. So on a multimeter, it indicates a mode where the meter can measure (probably crudely), the HFE of a transistor.

What is the current gain of a transistor?

Current gain is usually referred to as a β or hfe. Current is the ratio of the base current to the collector current and a measure of the amplifying ability of the transistor. If you want to use the transistor as an amplifier, then choose a transistor with higher current gain.

What is the current gain of a common collector amplifier?

The overall current gain is as follows: Voltage gain is still nearly equal to 1 if the entire assembly is connected to a load in common-collector fashion, although the load voltage will be a full 1.4 volts less than the input voltage shown in the figure below. Darlington pair based common-collector amplifier loses two VBE diode drops.

What is the common collector configuration of a transistor?

Below figure shows the common collector circuit for the transistor. Figure 1 shows a CC connection of PNP transistor and Figure 2 shows CC connection of NPN transistor. By the common collector, we can find the current amplification factor. The current amplification factor is the ratio of change in output current to change in input current.

Why is the gain of a bipolar transistor important?

In any circuit, the current gain of a bipolar transistor will be of paramount importance. Whether the circuit is common emitter, common collector, etc, and whether it uses NPN transistors or PNP transistors.