Why BJT is a current control device?

1 Answer

Answer :

BJT have three terminal emitter, base and collector. The collector current is the output current. The collector current (Ic) is controlled by base current hence BJT is called current controlled device.

Related questions

Last Answer : In  BJT  there  is  movement  of   electrons  and  holes   accros  the  junctions  which  is  basicaly  current  flow.

Last Answer : No, BJT is a current controlled device .

Last Answer : BJT is current controlled device.

Description : Power BJT is a current controlled device. Why?

Last Answer : Because the output (collector) current can be controlled by base current.

Description : why the bjt is known as current controlled device and fet is known as voltage controlled device ?

Last Answer : Ans- 1. In BJT because of the current the output will vary. 2. Where as in FET by means of Voltage the output is varied.

Description : An FET is a better chopper than a BJT because it has (A) lower offset voltage (B) higher series ON resistance (C) lower input current (D) higher input impedance

Last Answer : An FET is a better chopper than a BJT because it has lower offset voltage

Description : FET is advantageous in comparison with BJT because of  A) High input impedance B) High noise C) High gain bandwidth product D) Its current controlled behavior

Description : Compared to MOSFET operational amplifier, BJT operational amplifier has  A) Higher input resistance B) Higher slew rate C) Lower input current D) Higher voltage gain

Description : What is a BJT?

Last Answer : Bipolar Junction Transistor (BJT): BJT is a Bipolar device. (Uses both electrons and holes charge carrier for current conduction) Two Junctions (Emitter junction & collector ... mode (Current amplification) Cutoff mode (Open switch) Saturation mode (Close switch)

Description : Is BJT unipolar or bipolar Why?

Last Answer : Bipolar Junction Transistor (BJT) is a bipolar device because current is carried by both holes and electrons hence it is called bipolar.

Last Answer : Yes IGBT is costlier than BJT and MOSFET.

Last Answer : Yes BJT have internal capacitances.

Last Answer : BJT act as switch in saturation and  cutoff region ( ON state in saturation region and OFF state in cut-off region )

Last Answer : In cut-off region of BJT both the emitter-base junction and collector-base junction are reverse biased.

Last Answer : Active region of BJT act as amplifier.

Last Answer : Active , Saturation , Cut-off region of operations in BJT.

Last Answer : Yes BJT have second breakdown problem.

Last Answer : BJT have three terminals Base, emitter and collector.

Last Answer : When Q-point is at cut off region means it is just above the horizontal axis VCE

Last Answer : The proper flow of zero signal collector current and the maintenance of the proper collector emmiter voltage during passage of single called as transistor biasing

Last Answer : Beta is the current gain which is the ratio of collector current to base current.

Last Answer : BJT control the flow of electron so it is a active device.

Last Answer : Bipolar junction transistor

Last Answer : Transformer coupled amplifiers Direct coupled amplifiers Multistage amplifiers Darlington amplifiers Emmiter follower

Description : what are bjt transistors?

Last Answer : Bjt transistor is a type of transistor which  uses both electrons and hole charge carrier.bjts are used as switches and amplifiers.They amplify currents.

Description : Which is the most suitable power device for high frequency ( more 100 kHz) switching application? a) Power MOSFET b) BJT c) SCR d) UJT

Last Answer : Ans: Power MOSFET

Description : A modern power semiconductor device IGBT is combines the characteristics of a) BJT and MOSFET b) FCT and GTO c) SCR and MOSFET d) SCR and BJT

Last Answer : Ans: BJT and MOSFET

Description : A bipolar junction transistor (BJT) is used as a power control switch by biasing it in the cut-off region (OFF state) or in the saturation region (ON state). In the ON state, for ... base-collector junction is reverse biased (D) both the base-emitter and base-collector junctions are forward biased

Last Answer : A BJT is as a power control switch by biasing it in cut-off region (OFF state) or in the saturation region (ON state). In  ON state, for BJT both the base-emitter and base- collector junctions are forward biased

Description : Identify type of BJT configuration having following features : (i) BJT configuration having the least current gain. (ii) KIT configuration called as voltage follower. (iii) BJT ... configuration suitable for voltage amplification. (vi) BJT configuration having the least output impedance.  

Last Answer : (i) BJT configuration having the least current gain : Common Base Configuration  (ii) KIT configuration called as voltage follower: Common Collector Configuration  (iii) BJT ... Emitter Configuration  (vi) BJT configuration having the least output impedance: Common Collector Configuration

Description : Compare BJT common base configuration with common collector configuration on the basis of (i) Current gain (ii) Voltage gain (iii) Input impedance (iv) Output impedance

Last Answer : Parameter Common Base Common Collector Current gain Low (About 1) High (1+β) Voltage gain High 1  Input impedance  Low High Output impedance High Low

Description :  If the base current of a BJT is 250 µA and emitter current is 15 mA, then the common base current gain will be A) 0.98 B) 0.41 C) 59 D) 55  

Last Answer :  If the base current of a BJT is 250 µA and emitter current is 15 mA, then the common base current gain will be 0.98 

Description : The seven segment arrangement for numerical display on consoles, test meters and other applications can be either ________________. A. UJT or BJT B. BCD or OCD C. JFET or IGFET D. LED or LCD

Last Answer : Answer: D

Description : Draw the output characteristics of BJT in CE configuration and label various regions on it.

Last Answer :  output characteristics of BJT in CE configuration 

Description : State the applications of BJT.

Last Answer : Applications of BJT: 1. As a switch 2. As an amplifier 3. As a multivibrator 4. As a oscillator 5. As a timer circuit 6. As a Logic circuits 7. Delay circuits

Description : Draw the construction of BJT (NPN) and explain its working principle. State and explain different operating regions.

Last Answer : Construction of BJT (NPN): Working of NPN Transistor : The circuit diagram of the NPN transistor is shown in the figure below. The forward biased is applied across the emitter-base ... Zero with input current is Zero transistor in cut off. In this region transistor act as open switch

Description : Define the following with respect to BJT. (i) Input resistance (ii) Output resistance

Last Answer : Input resistance: It is the ratio of small change in emitter -to-base voltage(∆VEB) to the resulting change in emitter current (∆IE) for a constant collector to base voltage(VCB) ... of BJT is ratio of voltage between output terminal and common terminal to current through output terminal. 

Description : State 2 advantages of JFET over BJT.

Last Answer : Advantages of JFET over BJT: 1) High input impedance 2) Better thermal stability 3) Produce less noise 4) Smaller than BJT 5) Rugged in construction and simpler to fabricate 6) High degree of isolation between Input and Output. 

Description : Name two types of BJT &draw their symbols. 

Last Answer : Two types of BJT: * NPN * PNP 

Description : List the types of coupling used in BJT amplifier. 

Last Answer : Types of coupling used in BJT amplifier: i. Resistance capacitance (RC)coupling ii. Impedance coupling iii. Transformer coupling iv. Direct coupling

Description : Comparison of three configuration of BJT

Last Answer : Parameter Common Base(CB) Common Emitter (CE) Common collector (CC) Input terminal  Emitter Base Base Common terminal Base Emitter Collector Output terminal Collector Collector Emitter Gain factor Alpha(Ic/Ie) Beta(Ic/Ib) Gamma(Ie/Ib)