EDC UNIT IV- Transistor and FET
Characteristics
Lesson--5: Typical Transistor Junction
Lesson
Voltage Values
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EDC Lesson - " , Raj Kamal,
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90 A
70 A
50 A
30 A
Active region
IB= 10 A
IB= 0 A
Saturation
region
Limits of Operations
Pcmax= VCE.IC
= 10V. 10 mA= 100 mW
ICE0   ICB0
Cut-off region region
VCEsat  0.7 V
Output Characteristics (also called collector
characteristics) of Common Emitter for
100 mW transistor
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Range of operation





Should never exceed the maximum
Else output signal starts distorting (output
variation no longer proportional to input)
Pcmax= VCE.IC
VCEO or V (BR)CEO Maximum breakdown
voltage
common-collector-emitter Maximum
collector current (continuous collector
current) Icmax
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Operation condition
• At any point VCE.IC = 10V. 10 mA=
100 mW when specified maximum is
100 mW
•When Ic = 3mA,
VCE = 100 mW÷3mA= 33 V
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EDC Lesson - " , Raj Kamal,
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Bipolar junction transistor
ICEO ≤ IC ≤ ICmax
VCEsat ≤ VCE ≤ VCEmax

Common emitter VCE× IC ≤ PCmax

Common base VCB× IC ≤ PCmax


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Typical Transistor Junction Voltage
Values 2N4123 Maximum Rating
•emitter base Voltage VCEO = 5.0 V (dc)
•Collector Base Voltage VCBO = 40 V (dc)
•Collector emitter Voltage VCEO = 30 V (dc)
•Collector current continuous = 200 mA V (dc)
•Total device dissipation PD = 625 mW with
derate above 25°C = 5 mW / °C
•Operating and storage junction temperature –
55°C to 150°C
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Typical Transistor Junction Voltage
Values 2N4123 Thermal
Characteristic
• max Thermal resistance junction to case
RJC = 83.3 °C/W
• Max Thermal resistance junction to base
RJA = 200 °C/W
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Typical Transistor Junction Voltage Values
2N4123 Electrical characteristics OFF
Characteristics
• VBRCEO = Min 30 V collector-emitter
breakdown voltage (IC = 1.0 mA IE= 0)
• VBREBO = Min 30 V emitter-base breakdown
voltage (IC = 10 A IC= 0)
•VBRCBO = Min 40 V collector-base breakdown
voltage (IC = 0 IE= 10A)
• ICBO = max. 50 nA = 0.05 A collector cut off
Current (VCE = 20 V dc IE= 0)
• IEBO = max. 50 nA = 0.05 A collector cut off
Current
(VBE = 3.0EDCVLesson
dc- "I, CRaj=Kamal,
0)
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Typical Transistor Junction Voltage Values
2N4123 Electrical characteristics ON
Characteristics
• hFE = min 50, max 150 DC current gain (IC
= 2.0 mA dc VCE= 1.0 dc) = min 25, DC
current gain (IC = 50 mA dc VCE= 1.0 dc)
• VCEsat = max. 0.3 V dc collector-emitter
saturation voltage (IC = 50 mA dc IB= 5 mA
dc)
• VBEsat = max. 0.95 V dc base-emitter
saturation voltage (IC = 50 mA dc IB= 5 mA
dc)
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Typical Transistor Junction Voltage Values
2N4123 Electrical characteristics small signal
Characteristics
• fT = min 250 MHz current gain bandwidth
product (IC = 10 mA dc VCE= 20 V dc f= 100
MHz)
• Cobo = max 4.0 pF , output capacitance (IE = 0
VCB=5.0 V dc f= 100 MHz)
•Cibo = max 4.0 pF , input capacitance (IC = 0
VBE=0.5 V dc f= 100 MHz)
•Ccbo = max 4.0 pF , collector-base capacitance
(IE = 0 VCB=5.0 V dc f= 100 MHz)
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EDC Lesson - " , Raj Kamal,
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Typical Transistor Junction Voltage Values
2N4123 Electrical characteristics small signal
Characteristics
• hFE = min 50, max 200 DC small signal current
gain (IC = 2.0 mA dc VCE= 10 V dc f= 1.0 kHz)
• hFE = min 2.5 , high frequency current gain (IC
= 10 mA dc VCE= 20 V dc f= 100 MHz) = min
50 max. 200 small signal high frequency current
gain (IC = 2.0 mA dc VCE= 10 V dc f= 1.0kHz)
• Noise figure max. 6.0dB (IC = 100 A dc VCE=
5V dc Rs = 1.0 kOhm f= 1.0kHz)
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Summary
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We learnt ypical transistor characteristics
values
• Pcmax
• VECO
• VCBO
• VCEO
• hFE
• Ccb
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End of Lesson 5
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