BJT Exploration 1_NPN DC Biasing and CE Amp Configurations (1)

QUESTION 1 By referring to Figure Q1, determine: a) The Q-point values of Ic and VCE. b) Draw the DC load line and plot the Q-point based on answer from Q1(a). c) The diode emitter resistance, re and draw re transistor model (AC equivalent circuu). d) The input impedance, Zi as seen from the input voltage. e) The output impedance, Z, as seen from output. f) The voltage gain, Av and the current gain, A¡.

4. For the circuit shown in Figure, determine IC and VCB. Assume the transistor to be of Germanium.

All field-effect transistors are unipolar rather than bipolar devices. That is, the main current through them is comprised either of through an N-type semiconductor * ..... .....

Exercise 1:-

........ (Figure-1) R. RB= 380kN,Rc= 1kN B = 100, VBB = Vcc=12V RB ww Vec CC ......... I, V CE СЕ V ВЕ BB Q-1-b) Describe briefly the input / output characteristics and application of Common Emitter BJT Configuration

2. For the emitter-stabilized bias circuit, determine: a. IBo. b. Ica. c. VCEQ. d. Vc. e. VB. f. VE. 20 V 470 2 ICQ 270 k2 oVc VB B= 125 VCEQ OVE IBQ 2.2 k2

1. For the circuit in Figure 1: a) Calculate the input and output power if the input signal results in a base current of 6 mA. b) Calculate the input power dissipated by the circuit if Re is changed to 2kn. c) What maximum output power can be delivered by the circuit if Rg is changed to 2 ko? d) If the circuit is biased at its center voltage and center collector operating point, what is the input power for a maximum output power of 2W? 20V Re = 16 2 1.2 ks2 B- 40 100 µF Figure 1

Qa: A transistor dissipates 50W in an ambient temperature of 60°C, the thermal resistances are 0-0.5 °CW¹, 8ca-4 °CW. Determine the junction temperature without a heat sink. Determine the thermal resistance of the heat sink to avoid the junction temperature exceeding 180°C. )

Figure 1(a) shows the load line and operating point (Q point) for the common emitter amplifier circuits in Figure 1(b). Based on the Figure 1(a) and Figure 1(b), determine the a) supply voltage, Vec b) saturation current, Ieat c) collector-emitter voltage, VCEQ d) collector current, Ico e) base current, IB f) beta, B g) collector resistor, Rc h) base resistor, Rg

4 For the transistor shown in below figure, Calculate the value of R; that will just make the transistor work as closed switch. Hence Bpc = 80, VBE = 0.7V, VCE(sat) = 0.2V, Vcc = 12V, R. = 2.7KN. a) Calculate the I, and I.. Vcc RB Rc b) Calculate Rp.

Question 2 (a) To achieve correct operation when using a Bipolar Transistor how should the two p-n junctions be biased?

Using the characteristics of Figure Q1, determine the following for an emitter-bias configuration if a Q-point is defined at Ico=4 mA and VCEQ = 10 V. (i) (ii) (iii) (iv) (v) 10 9 8 7 6 5 4 3 2 Rc if Vcc=24 V and RE = 1.2 k. B at the operating point. RB. Power dissipated by the transistor. Power dissipated by the resistor Rc. Ic (mA) 5 10 110 μA 100 μA 15 90 μA 80 μ.Α. 70 μA 60 μA 20 Figure Q1 50 MA 40 μ.Χ. 30 μA 25 20 μ.. 10 με IB=0μA 30 VCE (V)

The transistor in the shown figure has Br =150. 1) What is the type of this configuration ? 2) Draw the DC equivalent circuit for the given figure. 3) Calculate the Q- point, and sketch it in the de load line (output I-V). 4) Calculate the ontput ac voltage and sketch it. 5) In which region does the transistor operate ? why. What is the function of this circuit 6) Discuss the function of Cl and C2 in this circuit. VCC 10V VcC R4 R2 R1 C1 TuF R6 24.7k0 1uF 2N2222A 02 Vrms R3 10ka RS C2 2.

Just need 1d and 1e answered.

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With Neat sketch explain the construction, operation, VI characteristics, application and features of the power semiconductor device which is having low on state loss and small switching frequency operation

Conclusion: Questions: [1] How to check transistor with help of multimeter? [2] How to check type of transistor (NPN or PNP) with help of multimeter? [3] Define current gain of the transistor in CE configuration. What is the DC current gain you obtain in this practical?

Q6:A) A transistor dissipates 50W in an ambient temperature of 60°C.The thermal resistance are exc-0.5 the junction temperature without a heat sink. Determine the thermal resistance of the heat sink to avoid the junction exceeding 170°C. °CW¹,0a-4°CW.Determine 5% single polver supply

Subject:Electronics Engineering  With a neat circuit diagram, explain the Voltage Divider Bias circuit using approximate analysis. Also derive the equation of stability (S) for Voltage Divider Bias circuit.

1. For a certain D-MOSFET, IDSS = 18 mA, and VGS = +10V. Vp =4V. a) Determine ID at VGS =+ 3V. b) Determine ID at VGS = -3V. %3D

Pls answer question d,e,f,g,h

3. Write down which transistor structure each curve characteristic belongs to in the figure. Ip -VGS -VGS +VGs (c) VGS (b) (a)

4. The transistor is a three-layer semiconductor device consisting of either - of material or 5. The input set for the common-base amplifier relates an input current various levels of output voltage 6. For BJT transistor ICBO =0.02 mA and ICEO= 4---- if B =60 to an input voltage for ----- ----

The term cut-off for a transistor refers to a. the transistor is at its operating point b. no current flow from emitter to collector c. maximum current flow from emitter to collector d. there is no base current

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power semiconductor device which is used metal in its PN junction. 2. Draw the equivalent circuit model and switching characteristics of the device which is used for low on state loss and high switching frequency operation.

Remove the bypass capacitor C2 and repeat part (c). Discuss about the effect of the bypass capacitor on the voltage Vout = Vin = AV =

VCC(V):15 ICsat(mA):8 Beta:150

2.2) Analyze the BJT circuit given in figure – 1. Determine the collector currents for DC current gains Boc = 100 and BDc = 200. Calculate the Q point of both cases. Determine the percentage change in Ic (collector current), Vcz (collector-emitter current). Use the below formulas: I -I V -V (-200) (-100) CE( -200) CE( -100) % Ic 100 ; % Ic -100 I (-100) Calculate the DC Load line of circuit. V CE( -100) Va=10" R2=1k2 RI=300k E 10V Figure – 1

c) Figure 2.3 shows the circuit diagram of a typical npn BJT common emitter amplifier. The values of RB1-30 kOhm, RB2=10.XY kOhm, Rc-3.XY kOhm, Ic=2.XY mA and Vcc=24 V. If the transistor current gain 3 = 50 determine using the full analysis and assuming VBE = 0.7 V the value of RE, hence identify the location of the Q-point (Ic, VCE, IB and VBE). Now sketch the AC circuit model of this amplifier and determine the value of the ac open circuit voltage gain Av and the ac short circuit current gain Ai. (Assume that Vth = 26 mV). Vin RB1 Cin lin RB2 -10 Rc VB RE + Vcc Vc Cout VE www li Figure 2.3 Vout Ce ¡out x=1 y=7

1. From the circuit shown in the figure, the transistor has a  β = 300.  The transistor is a. in saturation region b. in active region c. in cut-off region d. a switch2. Refer to the figure shown, the collector-base voltage of the transistor if β = 140 is  a. 5.28 V b. 5.98 V c. base voltage minus collector voltage d. -5.98 V e. collector-emitter minus emitter-base voltage3. In the circuit shown, the transistor has a β = 140 and that all the statement below about the transistor are true except  a. in the saturation region b. power delivered by the 5 V source is 1.79 mW c. operating in the active region d. power dissipation of the transistor is 300 mW

Q1:- find the emitter, base and collector currents and VE. (let any parameters if you need). + Vcc=6 V 2 k2 530 k2

4 For the transistor shown in below figure, Calculate the value of R, that will just make the transistor work as closed switch. Hence Bpc = 80, Vpp = 0.7V, Ver(sat) = 0.2V, Vec= 12V, R.= 2.7KN. a) Calculate the I, and Ie. Vcc b) Calculate Rp-