Advertisements
Advertisements
Question
Draw the circuit symbol for NPN and PNP transistors. What is the difference in the Emitter, Base, and Collector regions of a transistor?
Advertisements
Solution
The circuit symbols of the two types of transistors:
Figure (a)
Figure (b)
The difference in the Emitter (E), the Base (b), and the Collector (C) are as follows:
- Emitter: It is a thick heavily doped layer. This supplies a large number of majority carriers for the current flow through the transistor
- Base: It is the thin, lightly doped central layer.
- Collector: It is a thick and moderately doped layer. Its area is larger than that of the emitter and the base. This layer collects a major portion of the majority of carriers supplied by the emitter. The collector also helps dissipation of any small amount of heat generated.
APPEARS IN
RELATED QUESTIONS
In a BJT, the largest current flow occurs ______.
Why are the emitter, the base, and the collector of a BJT doped differently?
The common-base DC current gain of a transistor is 0.967. If the emitter current is 10mA. What is the value of base current?
Which method of biasing is used for operating a transistor as an amplifier?
In a common base configuration, the transistor has an emitter current of 10 mA and a collector current of 9.8 mA. The value of base current is ______
For a transistor β =75 and IE = 7.5 mA. The value of α is ______
Draw the circuit symbol of the PNP transistor.
Draw the circuit diagram to study the characteristic of the transistor in common emitter mode. Draw the input and output characteristics.
Transistor functions as a switch. Explain.
Assuming VCEsat = 0.2 V and β = 50, find the minimum base current (IB) required to drive the transistor given in the figure to saturation.
The condition to convert an amplified signal into an oscillating signal is ______
In the symbol for a transistor, the arrow head points in the direction of the ____________.
ln switching circuit, transistor is in ON state and values of IC and IB are 4.2 mA and 5 µA respectively and RC= l k`Omega` and RB= 300 k`Omega`. If VBE = 0.5 V, find the value of VBB.
In a transistor in CE configuration, the ratio of power gain to voltage gain is ____________.
Which of the following regions of a transistors are, respectively, heavily dopped and lightly dopped?
In a common emitter amplifier circuit using an n-p-n transistor, the phase difference between the input and the output voltages will be: ____________.
For a common emitter configuration, if 'α' and 'β' have their usual meanings, the correct relationship between 'α' and 'β' is ______.
In a silicon transistor, a change of 7.89 mA in the emitter current if produces a change of 7.8 mA in the collector current, then the base current must change by ____________.
A transistor when connected in common emitter mode has a ____________.
In a transistor, the thickness of the base region ____________.
In transistor amplifier, base-emitter junction is forward biased and collector emitter junction is reverse biased. The current gain is ______.
In the case of transistor, the relation between current ratios αdc and βdc is ______.
For an ideal diode, the current in the following arrangement is ______.
In common emitter amplifier, a change of 0.2 mA in the base current causes a change of 5 mA in the collector current. If input resistance is 2K `Omega` and voltage gain is 75, the load resistance used in the circuit is ______.
A transistor having α = 0.8 is connected in a common emitter configuration. When the base current changes by 6 mA, the change in collector current is ______
A common emitter amplifier circuit built using an n-p-n transistor is shown in the figure. Its DC current gain is 300, RC = 4 kΩ and VCC = 20 V. What is the minimum base current for VCE to reach saturation?
Define peak value of alternating signal.
Define β
