AB02
Common Base NPN
Transistor Characteristics
Analog Lab
Experiment Board
Ver. 1.0
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94-101, Electronic Complex, Pardesipura INDORE-452010, India.
Tel.: 91-731-2570301 Fax: 91-731-2555643
Email: info@scientech.bz Web: www.scientech.bz
AB02
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AB02
Common Base NPN Transistor Characteristics
AB02
TABLE OF CONTENTS
Table of Contents
Introduction..........................................................................................................................................4
THEORY.............................................................................................................................................6
EXPERIMENT....................................................................................................................................9
DATASHEET....................................................................................................................................16
WARRANTY....................................................................................................................................18
LIST OF SERVICE CENTERS.........................................................................................................19
List of Accessories.............................................................................................................................20
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AB02
Introduction
AB02 is a compact, ready to use Transistor Characteristics experiment board. This is useful for students to plot
different characteristics of NPN transistor in common base configuration and to understand various region of operation
of PNP transistor. It can be used as stand alone unit with external DC power supply or can be used with SCIENTECH
Analog Lab ST2612 which has built in DC power supply, AC power supply, function generator, modulation generator,
continuity tester, toggle switches, and potentiometer.
List of Boards :
Model
AB01
AB03
AB04
AB05
AB06
AB07
AB08
AB09
AB10
AB11
AB14
AB15
AB16
AB17
AB18
AB19
AB20
AB21
AB22
AB23
AB25
AB28
AB29
AB30
AB31
AB32
AB33
AB41
AB42
AB43
AB44
AB45
AB51
AB52
AB53
AB54
AB56
AB65
AB66
AB67
AB68
AB80
AB81
AB82
AB83
AB84
AB85
AB88
AB89
Name
Diode characteristics (Si, Zener, LED)
Transistor characteristics (CB PNP)
Transistor characteristics (CE NPN)
Transistor characteristics (CE PNP)
Transistor characteristics (CC NPN)
Transistor characteristics (CC PNP)
FET characteristics
Rectifier Circuits
Wheatstone Bridge
Maxwell’s Bridge
Darlington Pair
Common Emitter Amplifier
Common Collector Amplifier
Common Base Amplifier
Cascode Amplifier
RC-Coupled Amplifier
Direct Coupled Amplifier
Class a Amplifier
Class B Amplifier (push pull emitter follower)
Class C Tuned Amplifier
Phase Locked Loop (FM Demodulator & Frequency Divider / Multiplier)
Multivibrator ( Mono stable / Astable)
F-V and V-F Converter
V-I and I-V Converter
Zener Voltage Regulator
Transistor Series Voltage Regulator
Transistor Shunt Voltage Regulator
Differential Amplifier (Transistorized)
Operational Amplifier (Inverting / Non-inverting / Differentiator)
Operational Amplifier (Adder/Scalar)
Operational Amplifier (Integrator/ Differentiator)
Schmitt Trigger and Comparator
Active filters (Low Pass and High Pass)
Active Band Pass Filter
Notch Filter
Tschebyscheff Filter
Fiber Optic Analog Link
Phase Shift Oscillator
Wien Bridge Oscillators
Colpitt Oscillator
Hartley Oscillator
RLC Series and RLC Parallel Resonance
Kirchoff’s Laws (Kirchhoff’s Current Law & Kirchhoff’s Voltage Law)
Thevenin’s and Maximum power Transfer Theorem
Reciprocity and Superposition Theorem
Tellegen’s Theorem
Norton’s theorem
Diode Clipper
Diode Clampers
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AB02
AB90
AB91
AB92
AB93
AB96
AB97
AB101
AB102
AB106
Two port network parameter
Optical Transducer (Photovoltaic cell)
Optical Transducer (Photoconductive cell/LDR)
Optical Transducer (PhotoTransistor)
Temperature Transducer (RTD & IC335)
Temperature Transducer (Thermocouple)
DSB Modulator and Demodulator
SSB Modulator and Demodulator
FM Modulator and Demodulator
………… and many more
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THEORY
Transistor characteristics are the curves, which represent relationship between different dc currents and voltages of a
transistor. These are helpful in studying the operation of a transistor when connected in a circuit. The three important
characteristics of a transistor are:
1.
Input characteristic.
2.
Output characteristic.
3.
Constant current transfer characteristic.
Input Characteristic :
In common base configuration, it is the curve plotted between the input current (IE) verses input voltage (VBE) for
various constant values of output voltage (VCB).
The approximated plot for input characteristic is shown in Fig. 1. This characteristic reveal that for fixed value of
output voltage VCB, as the base to emitter voltage increases, the emitter current increases in a manner that closely
resembles the diode characteristics.
Fig. 1
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Output Characteristic :
This is the curve plotted between the output current IC verses output voltage VCB for various constant values of input
current IE.
The output characteristic has three basic region of interest as indicated in fig.2 the active region, cutoff region and
saturation region.
In active region the collector base junction is reverse biased while the base emitter junction if forward biased. This
region is normally employed for linear (undistorted) amplifier.
In cutoff region the collector base junction and base emitter junction of the transistor both are reverse biased. In this
region transistor acts as an OFF switch.
In saturation region the collector base junction and base emitter junction of the transistor both are forward biased. In
this region transistor acts as an ON switch.
Fig. 2
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Constant current transfer Characteristic :
This is the curve plotted between output collector current IC verses input emitter current IE for constant value of output
voltage VCB.
The approximated plot for this characteristic is shown in Fig 3.
Fig. 3
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EXPERIMENT
Objective :
To study the characteristics of NPN transistor in common base configuration and to evaluate
1. Input resistance
2. Output resistance
3. Current gain
Apparatus required :
1. Analog board of AB02.
2. DC power supplies +12V, -5V from external source or ST2612 Analog Lab.
3.
Digital Multimeter (3 numbers).
4.
2 mm patch cords.
Circuit diagram :
Circuit used to plot different characteristics of transistor is shown in Fig 4.
Fig. 4
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Procedure :
•
Connect -5V and +12V dc power supplies at their indicated position from external source or ST2612 Analog Lab.
•
To plot input characteristics proceed as follows :
1. Rotate both the potentiometer P1 and P2 fully in CCW (counter clockwise direction).
2. Connect Ammeter between test point 2 and 3 to measure input emitter current IE(mA).
3.
Short or connect a 2mm patch cord between test point 4 and 5
4. Connect one voltmeter between test point 1 and ground to measure input voltage VBE other voltmeter between test
point 6 and ground to measure output voltage VCB.
5.
Switch ON the power supply.
6. Vary potentiometer P2 and set a value of output voltage VCB at some constant value (1V, 2V…)
7. Vary the potentiometer P1 so as to increase the value of input voltage VBE from zero to 0.9V in step and measure
the corresponding values of input current IE for different constant value of output voltage VCB in an observation
Table 1.
8. Rotate potentiometer P1 fully in CCW direction.
9. Repeat the procedure from step 6 for different sets of output voltage VCB.
10. Plot a curve between input voltage VBE and input current IE as shown in Fig 1 using suitable scale with the help of
observation Table l. This curve is the required input characteristic.
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Observation Table 1 :
S.no.
Input
Input current IE(mA) at constant value of
voltage
output voltage
VBE
1.
0.0V
2.
0.1V
3.
0.2V
4.
0.3V
5.
0.4V
6.
0.5V
7.
0.6V
8.
0.7V
9.
0.8V
10.
0.9V
VCB = 1V
•
To plot output characteristics proceed as follows:
1.
Switch OFF the power supply.
VCB = 3V
VCB =5V
2. Rotate both the potentiometer P1 and P2 fully in CCW (counterclockwise direction).
3. Connect voltmeter between test point 6 and ground to measure output voltage VCB.
4. Connect one Ammeter between test point 2 and 3 to measure input current I E(mA) and other Ammeter between test
point 4 and 5 to measure output current IC(mA).
5.
Switch ON the power supply.
6. Vary potentiometer P1 and set a value of input current IE at some constant value (0mA, 1mA...)
7. Vary the potentiometer P2 so as to increase the value of output voltage VCB from zero to maximum value in step
and measure the corresponding values of output current IC for different constant value of input current IE in an
observation Table 2.
8. Rotate potentiometer P2 fully in CCW direction.
9. Repeat the procedure from step 6 for different sets of input current IE.
10. Plot a curve between output voltage VCB and output current IC as shown in Fig 2 using suitable scale with the help
of observation Table 2. This curve is the required output characteristic.
Observation Table 2 :
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Input
S.no.
Input current IC (mA) at constant value of
input voltage
voltage
VCB
1.
-1.0V
2.
0.0V
3.
0.5V
4.
1.0V
5.
2.0V
6.
3.0V
7.
4.0V
8.
5.0V
9.
6.0V
10.
7.0V
IE =
0mA
IE = 1mA IE = 2mA IE = 3mA IE = 4mA
•
To plot constant current transfer characteristics proceed as follows:
1.
Switch OFF the power supply.
2. Rotate both the potentiometer P1 and P2 fully in CCW (counter clockwise direction).
3. Connect voltmeter between test point 6 and ground to measure output voltage VCB.
4. Connect one Ammeter between test point 2 and 3 to measure input current IE (mA) and other Ammeter between
test point 4 and 5 to measure output current IC (mA).
5.
Switch ON the power supply.
6. Vary potentiometer P2 and set a value of output voltage VCB at maximum value.
7. Vary the potentiometer P1 so as to increase the value of input current I E from zero to 10 mA in step and measure
the corresponding values of output current IC in an observation Table 3.
8. Plot a curve between output current IC and input current IE as shown in Fig 3 using suitable scale with the help of
observation Table 3. This curve is the required Transfer characteristic.
Observation Table 3 :
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S.no.
Input
current
IE (mA)
1.
0.0 mA
2.
1.0 mA
3.
2.0 mA
4.
3.0 mA
5.
4.0 mA
6.
5.0 mA
7.
6.0 mA
8.
7.0 mA
9.
8.0 mA
10.
9.0 mA
Scientech Technologies Pvt. Ltd.
Output current IC (mA) at
constant output voltage
VCB = 10 V
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Calculations :
1. Input resistance: It is the ratio of change in the input voltage VBE to change in the input current IE at constant
value of output voltage VCB or it is the reciprocal of the slope obtained from the input characteristic.
Mathematically
To calculate input resistance determine the slope from the input characteristic curve obtained from observation
Table 1. Reciprocal of this slope will give the required input resistance.
2. Output resistance: It is the ratio of change in the output voltage VCB to change in the output current IC at constant
value of input current IE or it is the reciprocal of the slope obtained from the output characteristic.
Mathematically
To calculate output resistance determine the slope from the output characteristic curve obtained from
observation Table 2. Reciprocal of this slope will give the required output resistance.
3. Current gain: It is the ratio of change in the output current IC to change in the input current IE at constant value of
output voltage VCB or it is the slope obtained from the constant current transfer characteristic. It is denoted by αac
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Mathematically
αac = Slope of constant current transfer characteristic = ∆IC
∆IE
To calculate current gain, determine the slope from the constant current transfer characteristic curve obtained from
observation Table 3. This slope is the required current gain.
Results:
Input resistance Rin
= ________________
Output resistance Rout = ________________
Current Gain αac
= ________________
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DATASHEET
Scientech Technologies Pvt. Ltd.
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AB02
Scientech Technologies Pvt. Ltd.
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AB02
WARRANTY
1)
We guarantee the instrument against all manufacturing defects during 24 months from the date of sale by us or
through our dealers.
2)
The guarantee covers manufacturing defects in respect of indigenous components and material limited to the
warranty extended to us by the original manufacturer, and defect will be rectified as far as lies within our
control.
3)
The guarantee will become INVALID.
a) If the instrument is not operated as per instruction given in the instruction manual.
b) If the agreed payment terms and other conditions of sale are not followed.
c) If the customer resells the instrument to another party.
d) Provided no attempt have been made to service and modify the instrument.
4)
The non-working of the instrument is to be communicated to us immediately giving full details of the
complaints and defects noticed specifically mentioning the type and sr. no. of the instrument, date of purchase
etc.
5)
The repair work will be carried out, provided the instrument is dispatched securely packed and insured with
the railways. To and fro charges will be to the account of the customer.
DESPATCH PROCEDURE FOR SERVICE
Should it become necessary to send back the instrument to factory please observe the following procedure:
1)
2)
Before dispatching the instrument please write to us giving fully details of the fault noticed.
After receipt of your letter our repairs dept. will advise you whether it is necessary to send the instrument back
to us for repairs or the adjustment is possible in your premises.
Dispatch the instrument (only on the receipt of our advice) securely packed in original packing duly insured and freight
paid along with accessories and a copy of the details noticed to us at our factory address.
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LIST OF SERVICE CENTERS
1. Scientech Technologies Pvt. Ltd.
90, Electronic Complex
Pardesipura,
INDORE – 452010
2. Scientech Technologies Pvt. Ltd.
First Floor, C-19,
F.I.E., Patparganj Industrial Area,
DELHI – 110092
3. Scientech Technologies Pvt. Ltd.
New no.2, Old no.10, 4th street
Venkateswara nagar, Adyar
CHENNAI – 600025
4. Scientech Technologies Pvt. Ltd.
202/19, 4th main street
Ganganagar,
BANGALORE- 560032
5. Scientech Technologies Pvt. Ltd.
8,1st floor, 123-Hariram Mansion,
Dada Saheb Phalke road,
Dadar (East),
MUMBAI –400014
6. Scientech Technologies Pvt. Ltd.
988, Sadashiv Peth,
Gyan Prabodhini Lane,
PUNE – 411030
7. Scientech Technologies Pvt. Ltd
SPS Apartment, 1st Floor
2, Ahmed Mamoji Street,
Behind Jaiswal Hospital,
Liluah, HOWRAH-711204 W.B.
8. Scientech Technologies Pvt. Ltd
Flat No. 205, 2nd Floor,
Lakshminarayana Apartments
‘C’ wing, Street No. 17,
Himaytnagar,
HYDERABAD- 500029
Scientech Technologies Pvt. Ltd.
Ph : (0731) 2570301
Email : info@scientech.bz
Ph : (011) 22157370, 22157371
Fax : (011) 22157369
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Ph : (044) 42187548, 42187549
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Ph : +913355266800
Email : kolkata@scientech.bz
Ph : (040) 55465643
Email : hyd@scientech.bz
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AB02
List of Accessories
1.
2mm Patch cord (red) .............................................................2 Nos.
2.
2mm Patch cord (black) ..........................................................2 Nos.
3.
2mm Patch cord (blue) ...........................................................1 Nos.
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