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    I CYCLE EXPERIMENTS

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    Symbolic representation of PN Junction Diode

    Circuit Diagram:

    Fig-1 Diode under forward bias condition

    Fig-2 Diode under reverse bias condition

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    -No:

    Date:

    CHARACTERISTICS OF PN JUNCTION DIODE

    Aim:

    To study and plot volt-ampere characteristic of PN Junction Diode and determine its

    Q-point and dynamic resistance.

    Apparatus Required:

    S. No Items Range Type Quantity

    1 Diode IN4007 1

    2 Regulated Power supply 0-30V Single 1

    3 Ammeter 0-50mA MC 1

    4 Voltmeter

    (0-10)V

    (0-1)V MC 1

    5 Bread Board 1

    6 Connecting Wires Single strand as req.

    Formula used:Static Resistance, R=Vf/If

    Dynamic Resistance, r =Vf/If

    To find DC Load Line: E= (RfIf) +Vd

    Theory:

    Forward Bias Condition:

    When positive terminal of the battery is connected to the P type and the negative

    terminal to N type of the PN junction diode, the bias applied is known as forward bias.

    Operation:

    The applied potential with the external battery acts in opposition to the internal

    potential barrier. The applied positive potential repels the holes in P type region so that the

    holes move towards the junction and the applied negative potential repels the electrons in the

    N type region and the electrons move towards the junction. Eventually, when the applied

    potential is more than the internal barrier potential, the depletion region and internal potential

    barrier disappear.

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    At the cut in voltage or threshold voltage (V r), the potential barrier is overcome and

    the current through the junction starts to increase rapidly.

    Model graph:

    Tabulation:

    Forward bias: Reverse bias:

    S. No Voltage (Vf)

    in volts

    Current (If)

    in mA

    S.No Voltage (Vr)

    in volts

    Current (Ir)

    in uA

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    Reverse bias condition:

    When the negative terminal of the battery is connected to the P type and the positive

    terminal to the N type of the PN junction diode, the bias applied is known as reverse bias.

    Operation:

    Under applied reverse bias, holes which form the majority carriers of the P side move

    towards the negative terminal of the battery and electrons which forms the majority carriers

    of the N side are attracted towards the positive terminal of the battery. Hence, the width of

    the depletion region which is depleted of mobile charge carriers increases. Thus, the electric

    field produced by applied reverse bias, is in the same direction as the electric field of the

    potential barrier.

    Therefore no current flows in the external circuit. Consequently, the minority carriers

    will flows towards their majority carrier side gives rise to small reverse current. This current

    is known as reverse saturation current, Io.

    Once the electric field intensity increases beyond a critical level, the p-n junction

    depletion zone breaks-down and current begins to flow, usually by either the Zener or

    avalanche breakdownprocesses.

    http://en.wikipedia.org/wiki/Zener_breakdownhttp://en.wikipedia.org/wiki/Avalanche_breakdownhttp://en.wikipedia.org/wiki/Avalanche_breakdownhttp://en.wikipedia.org/wiki/Zener_breakdown
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    Procedure:

    Forward bias:

    Connections are made as per the circuit diagram fig-1. Input voltage is varied corresponding diode voltage and current readings are

    tabulated.

    V-I characteristic of diode under forward bias condition is plotted.Reverse bias:

    Connections are made as per the circuit diagram fig-2. Input voltage is varied corresponding diode voltage and current readings are

    tabulated. V-I characteristic of diode under reverse bias condition is plotted.

    Viva Questions:

    1. What is meant by PN junction diode?2. What is meant by barrier potential and threshold voltage?3. What are the different types of breakdown occur in diode?4. Give the expression for diode current equation and width of the depletion region.5. What are the classifications of semiconductor devices?6. What is meant by transient capacitance and diffusion capacitance?

    Result:

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    Symbolic representation of Zener Diode

    Circuit Diagram:

    Under Forward Bias Condition:

    Under Reverse Bias Condition:

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    Ex-No:

    Date:

    CHARACTERISTIC OF ZENER DIODE

    Aim:

    To study and plot volt-ampere characteristic of Zener Diode and find its dynamic

    resistance.

    Apparatus Required:

    S. No Items Range Type Quantity1 Zener Diode Z 6V8 1

    2 Regulated Power supply 0-30V Single 1

    3 Ammeter 0-50mA MC 1

    4 Voltmeter 0-10V MC 1

    5 Bread Board 1

    6 Connecting Wires Single strand as req.

    Theory:

    Zener diode is a special diode operating in the breakdown region of the ordinary

    diode. This diode is heavily doped when compared to ordinary diode. It exhibits almost the

    same properties, except the device is special in the reverse direction if the voltage is larger

    than the breakdown voltage known as "Zener knee voltage" or "Zener voltage".

    They are widely used to regulate the voltage across a circuit. When connected in

    parallel with a variable voltage source so that it is reverse biased, a Zener diode conducts

    when the voltage reaches the diode's reverse breakdown voltage.

    http://en.wikipedia.org/wiki/Breakdown_voltagehttp://en.wikipedia.org/wiki/Breakdown_voltage
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    Model Graph:

    Tabulation:

    Forward bias Condition:

    S.No Voltage (Vf) in

    volts

    Current (If) in

    mA

    Reverse Bias Condition:

    S.No Voltage (Vr) in

    volts

    Current (Ir) in mA

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    Procedure:

    Forward Bias:

    Connections are made as per the circuit diagram. Input voltage is varied corresponding diode voltage and current readings are

    tabulated.

    V-I characteristic of diode under forward bias condition is plotted. Find the dynamic resistance r =Vf/If

    Reverse Bias:

    Connections are made as per the circuit diagram. Input voltage is varied corresponding diode voltage and current readings are

    tabulated.

    V-I characteristic of diode under reverse bias condition is plotted. Find the dynamic resistance r = Vz/ Iz.

    Result:

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    Circuit Diagram:

    Half Wave Rectifier without Filter:

    Half Wave Rectifier with Filter:

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    Ex. No.:

    DATE:

    SINGLE PHASE HALF WAVE RECTIFIER WITH AND WITHOUT FILTER

    Aim:

    To obtain DC signal from AC signal by using half wave rectifier without and with

    filter and obtain ripple factor and Efficiency.

    Materials Required:

    S No Item Range Specification Qty

    1. Diode IN4007 1

    2. Transformer 230V/(09)V 1

    3. CRO 030 MHz 1

    4. Resistor 1k 1

    5. Bread board 1

    6. Ammeter 0-50mA MC 1

    7. Voltmeter 0-30V MC 1

    8. Connecting wires Single stand As req.

    9. Capacitor 22 F 1

    Theory:

    In a HWR, the diode is forward biased only during the positive half cycle of the input

    signal. The diode conducts and current flows through the load only for the positive half cycle

    of input voltage. During the negative half cycle the diode is reversed biased and the diode

    behaves as an open circuit. Hence there is no current flow through the load. The output DC

    signal is the pulsating DC signal. By using the basic capacitive filter we can convert the

    pulsating DC into pure DC signal.

    When no filter circuit is present output voltage Vdc = Vm/

    The RMS value of the secondary voltage of the transformer is V rms = Vm/2.

    Formula Used:

    The output DC power Pdc = VdcIdc

    The output AC power Pac=VrmsIrms

    Efficiency()= Pdc/ Pac

    Form Factor(FF)= Vrms/Vdc

    Ripple Factor = [(Vrms/ Vdc)21]1/2 or [(FF2-1)]1/2

    Transformer Utilization ratio(TUF)= Pdc/VsIs

    Where,Vs & Is are rms voltage and rms current of the transformer secondary respectively

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    Model Graph:

    Input Wave Form:

    Output Wave Form without Filter:

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    Procedure:

    1. The circuit connections are given as per the circuit diagram.2. The supply voltage is switched on.3. The DC voltage and current are noted down.4. By using the CRO observe the wave forms.5. From the tabulated reading find the ripple factor and Efficiency

    Viva Questions:

    1. What is rectifier?2. Explain the following terms:

    I. Ripple factorII. Peak Inverse Voltage

    III. Average voltage and currentIV. Rectifier efficiencyV. Ripple voltage

    3. What is the main disadvantage of HWR?4. What is called % regulation?

    Result:

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    Output Wave Form with

    Filter:

    Tabulation:

    Without filter:

    Vm(V) Vrms(V) Vdc(V) Ripple factor Efficiency

    With filter:

    Vm(V) Vrms(V) Vdc (V) Ripple factor Efficiency

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    Circuit Diagram:

    Full Wave Rectifier without Filter:

    Center tap transformer

    230V/(12V-0V-12V)

    Full Wave Rectifier with Filter:

    Center tap transformer

    230V/(12V-0V-12V)

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    Ex. No.:

    DATE:

    SINGLE PHASE FULL WAVE RECTIFIER WITH AND WITHOUT FILTER

    Aim:

    To obtain DC signal from AC signal by using half wave rectifier without and with

    filter and obtain ripple factor and Efficiency.

    Materials Required:

    S No Item Range Specification Qty

    1. Diode IN4007 2

    2. Transformer 230V/(09)V 1

    3. CRO 030 MHz 1

    4. Resistor 1k 1

    5. Bread board 1

    6. Ammeter 0-50mA MC 1

    7. Voltmeter 0-30V MC 1

    8. Connecting wires Single stand As req.

    9. Capacitor 22 F 1

    Theory:

    In FWR, current flows through the load in the same direction for both the half cycles

    of the input voltage. This can be achieved with two diodes working alternatively. During the

    positive half cycle diodes D1 and D2 conducts and supplies current to the load. During the

    negative half cycle diodes D3 and D4 will conducts and current flows through the load in the

    same direction. Hence the output obtained as the full wave rectifier DC voltage. The output

    DC signal is the pulsating DC signal. By using the basic capacitive filter we can convert the

    pulsating DC into pure DC signal.

    When no filter circuit is present output voltage Vdc = 2Vm/.

    The RMS value of the secondary voltage of the transformer is Vrms = Vm/2.

    Formula Used:

    Ripple Factor = [(Vrms/ Vdc)21]1/2.

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    Model Graph:

    Input Wave Form:

    Output Wave Form without Filter:

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    Output Wave Form with Filter:

    Tabulation:

    Without filter:

    Vm Vrms Vdc Ripple factor Efficiency

    With filter:

    Vm Vrms Vdc Ripple factor Efficiency

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    Procedure:

    1. The circuit connections are given as per the circuit diagram.2. The supply voltage is switched on.3. The DC voltage and current are noted down.4. By using the CRO observe the wave forms.5. From the tabulated reading find the ripple factor and percentage regulation.

    Viva Questions:

    1. What are the various types of filters used in rectifier circuit?2. What is surge current?3. How the surge current can be eliminated?4. State the expression for ripple factor.5. Explain the effect of load resistance and filter capacitance on the load voltage.

    Result:

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    Pin Configuration for BC 547 NPN TRANSISTOR

    Circuit Diagram:

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    Ex-No:

    Date:

    CHARACTERISTIC OF TRANSISTOR IN CE CONFIGURATION

    Aim:

    To study and plot the input and output characteristics of bipolar junction transistor in

    common emitter configuration and determine its hybrid parameters.

    Apparatus Required:

    Formula Used:

    Input Resistance, hie= Vbe/ Ib at constant Vce

    Reverse transfer ratio, hre= Vbe/ Vce at constant Ib

    Output Conductance, hoe= Ic/ Vce at constant Ib

    Forward Current Transfer Ratio, hfe= Ic / Ibat constant Vce

    Theory:

    A bipolar (junction) transistor (BJT) is a type of transistor. It is a three-terminaldevice constructed ofdopedsemiconductormaterial and may be used in amplifying or

    switching applications.

    S. No Items Range Type Quantity

    1 Transistor BC107 1

    2 Regulated Power Supply (0-30V) Dual 1

    3 Resistor 1K 2

    4 Ammeter (0-50mA) MC 2

    5 Voltmeter (0-3V) MC 1

    6 Voltmeter (0-30V) MC 17 Bread Board 1

    8 Connecting wires single strand AS req.

    http://en.wikipedia.org/wiki/Transistorhttp://en.wikipedia.org/wiki/Doping_%28Semiconductors%29http://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Electronic_amplifierhttp://en.wikipedia.org/wiki/Electronic_amplifierhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Doping_%28Semiconductors%29http://en.wikipedia.org/wiki/Transistor
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    Model Graph:

    Input Characteristic: Output Characteristics:

    Tabulation:

    Input Characteristic:

    Output Characteristics:

    S. NoIb= Ib= Ib=

    Vce(V)

    Ic(mA)

    Vce(V)

    Ic(mA)

    Vce(V)

    Ic(mA)

    S. NoVce= Vce= Vce=

    Vbe(V)

    Ib(mA)

    Vbe(V)

    Ib(mA)

    Vbe(V)

    Ib(mA)

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    Although a small part of the transistor current is due to the flow ofmajority carriers,most of the transistor current is due to the flow of minority carriers and so BJTs are

    classified as minority-carrier devices.

    Forward-active (or simply, active): The emitterbase junction is forward biased andthe basecollector junction is reverse biased. Most bipolar transistors are designed to

    afford the greatest common-emitter current gain, F, in forward-active mode. If this is

    the case, the collectoremitter current is approximately proportional to the base

    current, but many times larger, for small base current variations.

    Reverse-active (or inverse-active or inverted): By reversing the biasing conditions ofthe forward-active region, a bipolar transistor goes into reverse-active mode. In this

    mode, the emitter and collector regions switch roles. Because most BJTs are designed

    to maximize current gain in forward-

    Active mode, the F in inverted mode is several (23 for the ordinary germaniumtransistor) times smaller. This transistor mode is seldom used, usually being

    considered only for failsafe conditions and some types of bipolar logic. The reverse

    bias breakdown voltage to the base may be an order of magnitude lower in this region.

    Saturation Region: With both junctions forward-biased, a BJT is in saturation modeand facilitates high current conduction from the emitter to the collector. This mode

    corresponds to a logical "on", or a closed switch.

    Cutoff Region: In cutoff, biasing conditions opposite of saturation (both junctionsreverse biased) are present. There is very little current flow, which corresponds to a

    logical "off", or an open switch.

    Active Region: In active region, the emitter base junction is forward bias and thecollector base junction is reverse bias.

    Common Emitter Configuration: The input is connected between base and emitterwhile output is connected between collector and emitter. Emitter is common to both

    input and output circuit.

    Input Characteristic: The curve drawn between base current, (Ib) and base-emittervoltage (Vbe) and base current Ib at constant collector-emitter voltage (Vce).

    Output Characteristic: It is the curve drawn between collector current Ic andcollector-emitter voltage Vce for a constant base current Ib.

    http://en.wikipedia.org/wiki/Majority_carrierhttp://en.wikipedia.org/wiki/Minority_carrierhttp://en.wikipedia.org/wiki/Proportionality_%28mathematics%29http://en.wikipedia.org/wiki/Proportionality_%28mathematics%29http://en.wikipedia.org/wiki/Minority_carrierhttp://en.wikipedia.org/wiki/Majority_carrier
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    Procedure:

    Input Characteristic:

    Connections are made as per the circuit diagram. Keeping the collector-emitter voltage (Vce) constant varies the emitter-base voltage

    (Vbe) and note down the base current (Ib).

    Repeat the step2 for varies values of constant Vce and tabulate the readings. Now plot the graph for the tabulated values.Output Characteristic:

    Connections are made as per the circuit diagram. Keeping the base current (Ib) constant vary collector-emitter voltage (Vce) tabulate

    collector current (Ic).

    Repeat the step 2 for varies values of constant Ib and tabulate the readings. Now plot the graph for the tabulated values.

    Viva Questions:

    1. What is Transistor?2. Explain the working of NPN transistor?3. What is reverse saturation current?4. What is meant by emitter efficiency?5. Give the hparameters of CE configuration?6. Explain the input and output characteristics of CE configuration.

    Result:

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    Pin Configuration for BC 547 NPN TRANSISTOR

    Circuit Diagram:

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    Ex-No:

    Date:

    CHARACTERISTIC OF TRANSISTOR IN CB CONFIGURATION

    Aim:

    To study and plot the input and output characteristics of bipolar junction transistor in

    common base configuration.

    Apparatus Required:

    Formula Used:

    (1) Input impedance hib= Veb/ Ie, with Vcbconstant

    (2) Output conductance hob = Ic/ Vcb, with Ie constant

    (3) Forward current gain hfb = Ic/ Ie , with Vcbconstant

    (4) Reverse Voltage gain hrb

    = Veb

    / Vcb

    , with Ieconstant

    Theory:

    A bipolar (junction) transistor (BJT) is a type of transistor. It is a three-terminaldevice constructed ofdoped semiconductormaterial and may be used in amplifying or

    switching applications.

    S. No Items Range Type Quantity

    1 Transistor BC107 1

    2 Regulated Power Supply (0-30V) Dual 1

    3 Resistor 1K 2

    4 Ammeter (0-50mA) MC 2

    5 Voltmeter (0-30V) MC 2

    6 Bread Board 1

    7 Connecting wires single stand AS req.

    http://en.wikipedia.org/wiki/Transistorhttp://en.wikipedia.org/wiki/Doping_%28Semiconductors%29http://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Electronic_amplifierhttp://en.wikipedia.org/wiki/Electronic_amplifierhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Doping_%28Semiconductors%29http://en.wikipedia.org/wiki/Transistor
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    Model Graph:

    Input Characteristics: Output Characteristics:

    Tabulation:

    Input Characteristic:

    S. NoVcb= Vcb= Vcb=

    Veb(V)

    Ie(mA)

    Veb(V)

    Ie(mA)

    Veb(V)

    Ie(mA)

    Output Characteristics:

    S. NoIe = Ie = Ie =

    Vcb(V)

    Ic(mA)

    Vcb(V)

    Ic(mA)

    Vcb(V)

    Ic

    (mA)

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    Although a small part of the transistor current is due to the flow ofmajority carriers,most of the transistor current is due to the flow of minority carriers and so BJTs are

    classified as minority-carrier devices.

    Forward-active (or simply, active): The emitterbase junction is forward biased andthe basecollector junction is reverse biased. Most bipolar transistors are designed to

    afford the greatest common-emitter current gain, F, in forward-active mode. If this is

    the case, the collectoremitter current is approximately proportional to the base

    current, but many times larger, for small base current variations.

    Reverse-active (or inverse-active or inverted): By reversing the biasing conditions ofthe forward-active region, a bipolar transistor goes into reverse-active mode. In this

    mode, the emitter and collector regions switch roles. Because most BJTs are designed

    to maximize current gain in forward-active mode, the F in inverted mode is several

    (23 for the ordinary germanium transistor) times smaller. This transistor mode is

    seldom used, usually being considered only for failsafe conditions and some types of

    bipolar logic. The reverse bias breakdown voltage to the base may be an order of

    magnitude lower in this region.

    Saturation Region: With both junctions forward-biased, a BJT is in saturation modeand facilitates high current conduction from the emitter to the collector. This mode

    corresponds to a logical "on", or a closed switch.

    Cutoff Region: In cutoff, biasing conditions opposite of saturation (both junctionsreverse biased) are present. There is very little current flow, which corresponds to a

    logical "off", or an open switch.

    Common Base Configuration: The input is connected between base and emitterwhile output is connected between collector and base. Base is common to both input

    and output circuit.

    Input Characteristic: The curve drawn between base current, (Ib) and base-emittervoltage (Vbe) and base current Ib at constant collector-base voltage (Vcb).

    Output Characteristic: It is the curve drawn between collector current Ic andcollector-emitter voltage (Vce) for a constant base current (Ie).

    http://en.wikipedia.org/wiki/Majority_carrierhttp://en.wikipedia.org/wiki/Minority_carrierhttp://en.wikipedia.org/wiki/Proportionality_%28mathematics%29http://en.wikipedia.org/wiki/Proportionality_%28mathematics%29http://en.wikipedia.org/wiki/Minority_carrierhttp://en.wikipedia.org/wiki/Majority_carrier
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    Procedure:

    Input Characteristic:

    Connections are made as per the circuit diagram. Keeping the collector-base voltage (Vcb) constant varies the emitter-base voltage

    (Vbe) and note down the emitter current (Ie).

    Repeat the step2 for varies values of constant Vcband tabulate the readings. Now plot the graph for the tabulated values.Output Characteristic:

    Connections are made as per the circuit diagram. Keeping the emitter current (Ie) constant varies collector-base voltage (Vcb) tabulate

    collector current (Ic).

    Repeat the step 2 for varies values of constant Ie and tabulate the readings. Now plot the graph for the tabulated values.

    Viva Questions:

    1. What is base width modulation?2. Explain Transfer Resistance.3. Explain the construction of PNP transistor.4. Give the hparameters of CB configuration?5. Explain the input and output characteristics of CB configuration.

    Result:

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    Pin Configuration for BC 547 NPN TRANSISTOR

    Circuit Diagram:

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    EX.No:

    Date:

    CHARACTERISTICS OF COMMON COLLECTOR CONFIGURATION

    AIM:

    To determine the characteristics of BJT under Common collector configuration.

    Apparatus required:

    S.No. Apparatus required Range Quantity

    1. RPS (0-30)V 22. Voltmeter (0-1)V 2

    3. Ammeter (0-100)A 2

    4. Resistance 10K 1

    5. Transistor BC 107 1

    6. Bread board 1

    7. Connecting wires As required

    Theory:

    A bipolar (junction) transistor (BJT) is a type of transistor. It is a three-terminaldevice constructed ofdoped semiconductormaterial and may be used in amplifying or

    switching applications.

    Although a small part of the transistor current is due to the flow ofmajority carriers,most of the transistor current is due to the flow of minority carriers and so BJTs are

    classified as minority-carrier devices.

    Forward-active (or simply, active): The emitterbase junction is forward biased andthe basecollector junction is reverse biased. Most bipolar transistors are designed to

    afford the greatest common-emitter current gain, F, in forward-active mode. If this is

    the case, the collectoremitter current is approximately proportional to the base

    current, but many times larger, for small base current variations.

    http://en.wikipedia.org/wiki/Transistorhttp://en.wikipedia.org/wiki/Doping_%28Semiconductors%29http://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Electronic_amplifierhttp://en.wikipedia.org/wiki/Majority_carrierhttp://en.wikipedia.org/wiki/Minority_carrierhttp://en.wikipedia.org/wiki/Proportionality_%28mathematics%29http://en.wikipedia.org/wiki/Proportionality_%28mathematics%29http://en.wikipedia.org/wiki/Minority_carrierhttp://en.wikipedia.org/wiki/Majority_carrierhttp://en.wikipedia.org/wiki/Electronic_amplifierhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Doping_%28Semiconductors%29http://en.wikipedia.org/wiki/Transistor
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    MODEL GRAPH FOR CC CONFIGURATION:

    INPUT CHARACTERISTICS

    OUTPUT CHARACTERISTICS

    Tabulation :

    Input Characteristics:

    S. NoVce= Vce= Vce=

    Vbc(V)

    Ib(mA)

    Vbc(V)

    Ib(mA)

    Vbc(V)

    Ib(mA)

    Output Characteristics:

    S. NoIb = Ib= Ib=

    Vce(V)

    Ie(mA)

    Vce(V)

    Ie(mA)

    Vce(V)

    Ie(mA)

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    Reverse-active (or inverse-active or inverted): By reversing the biasing conditions ofthe forward-active region, a bipolar transistor goes into reverse-active mode. In this

    mode, the emitter and collector regions switch roles. Because most BJTs are designed

    to maximize current gain in forward-active mode, the F in inverted mode is several

    (23 for the ordinary germanium transistor) times smaller. This transistor mode is

    seldom used, usually being considered only for failsafe conditions and some types of

    bipolar logic. The reverse bias breakdown voltage to the base may be an order of

    magnitude lower in this region.

    Saturation Region: With both junctions forward-biased, a BJT is in saturation modeand facilitates high current conduction from the emitter to the collector. This mode

    corresponds to a logical "on", or a closed switch.

    Cutoff Region: In cutoff, biasing conditions opposite of saturation (both junctionsreverse biased) are present. There is very little current flow, which corresponds to a

    logical "off", or an open switch.

    Common Collector Configuration: The input is connected between base andcollector while output is connected between collector and emitter. Collector is

    common to both input and output circuit.

    Input Characteristic: The curve drawn between base current, (Ib) and base-collectorvoltage (Vbc) at constant collector-emitter voltage (Vce).

    Output Characteristic: It is the curve drawn between emitter current Ie andcollector-emitter voltage (Vce) for a constant base current (Ie).

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    PROCEDURE:

    Input characteristics:

    1. Keeping the voltage across collector to emitter (Vce) as constant, tabulate the

    values of base current for various values of base collector voltage (Vbc).

    2. Repeat the same procedure for various values of Vce.

    Output characteristics:

    1. Keeping the base current as constant, tabulate the values of emitter current (Ie)

    for various values of collector emitter voltage (Vce).

    2. Repeat the same procedure for various constant values of base current (Ib).

    Result:

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    Circuit Diagram:

    Model Graph:

    Tabulation:

    S. No Frequency(Hz) Current(mA)

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    Ex-No:

    Date:

    FREQUENCY RESPONSE OF SERIES AND PARALLEL RESONANCE

    Aim:

    To obtain the frequency response of parallel and series resonance circuits.

    Apparatus Required:

    S. No Items Range Type Quantity

    1 Function Generator (0-30MHz) 1

    2 Ammeter (0-5)mA MC 1

    3 Resistor 1K 14 Capacitor 0.07F 1

    5 Inductor 50 mH 1

    6 Bread Board 1

    7 Connecting Wires Single stand as req.

    Statement:

    Resonance is defined as a phenomenon in which the applied voltage and

    resulting current are in phase with each other. In other words, an ac circuit is said to bein resonance it exhibits unity power factor condition, which means the applied voltage

    and resulting current are in phase.

    In ac RLC series circuit under the condition of resonance, the inductive reactance

    gets cancelled with capacitive reactance and the impedance of a ac circuit consists only

    resistance.

    Resonance is series circuits are referred as series resonance or simply

    resonance.

    Characteristic of series resonance:

    Input impedance is purely resistive. Applied voltage and current are in phase. Circuit current is maximum. Input impedance is equal to resistance. Power factor is unity Resonance frequency, Fr = 1/(2LC).

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    Circuit Diagram for Parallel Resonance:

    Model Graph:

    Tabulation:

    S.No Frequency(Hz) Voltage(volts)

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    Parallel resonant circuit:

    Similar to a series ac circuit there can be a resonance in parallel circuit. When the

    power factor of a parallel ac circuit is unity, ie the voltage and total current are in phase

    at particular frequency then the parallel circuit is said to be at resonance occurs is calledresonant.

    Procedure:

    Series circuit:

    Connections are made as per the circuit diagram. Switch on the function generator and set the sinusoidal input voltage of

    2v in function generator.

    Set the function generator to a low frequency of 500 Hz. Note the current and tabulate the readings. Increase the frequency in steps upto 7 kHz. Repeat the step and draw the graph between frequency Vs current.

    Parallel circuit:

    Connections are made as per the circuit diagram. Switch on the function generator and set sinusoidal input voltage of in

    function generator.

    Set the function generator to a low frequency of 500 Hz. Note the voltage and tabulate the readings. Increase the frequency in steps upto 10 kHz. Repeat the step and draw the graph between frequency Vs voltage.

    Result:

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    CIRCUIT DIAGRAM:

    HIGH PASS FILTER:

    LOW PASS FILTER:

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    Ex.No:

    Date :

    REALISATION OF PASSIVE FILTERS

    AIM:

    To determine experimentally the frequency response of low pass and high pass filters and

    note down the cut-off frequency

    Apparatus Required:

    THEORY:

    HIGH PASS FILTER:

    This filter allows only high frequency of AC voltage and rejects the low frequency

    components at the output. We know that Xc

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    TABULATION:

    HIGH PASS FILTER LOW PASS FILTER

    MODEL GRAPH:

    Input voltage

    in Volts

    Frequency

    in hz

    Output

    voltage

    in volts

    Gain=

    20log(Vo/Vin)

    In db

    Input voltage

    in Volts

    Frequency

    in hz

    Output

    voltage

    in volts

    Gain=

    20log(Vo/Vin)

    In db

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    Procedure:

    1. The connections are made as per the Circuit diagram2. Switch on the power supply and increase the input frequency in steps of 100HZ and

    note down the corresponding output voltage in the voltmeter

    3. Calculate the gain value4. Draw the Graph between frequency Vs gain

    Result:

    HIGH PASS FILTER:

    Designed cut-off frequency.Hz

    obtained cut-off frequency.Hz

    LOW PASS FILTER:

    Designed cut-off frequency.Hz

    obtained cut-off frequency.Hz