Summary: Summary: The family of Output Curves and the incremental model of Triode, Pentode ;
LECTURE NO.2_PartA
Analog Electronics Lecture 2_PartA_I-V characteristics of Vacuum Tubes
Key words; Triode, Pentode;
Summary: The family of Output Curves and the incremental model of Triode, Pentode ;
All the amplifying devices are Active Devices. Vacuum Tubes, Bipolar Junction Transistor(BJT) and Field Effect Transistors(FET) belong to this group. Whereas Resistors, Inductors and Capacitors are passive devices.
OUTPUT FAMILY OF CURVES OF ACTIVE DEVICES
TRIODE OUTPUT CHARACTERISTICS
The general output characteristics of a triode is as follows:
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But the idealized output characteristics would look like:
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Thus triode is a voltage controlled voltage source.
The incremental model of a triode is:
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Where rp =plate resistance
µ = Amplification factor
PENTODE OUTPUT CHARACTERISTICS
A pentode has 5 plates. They are cathode, grid, screen, suppressor and anode.
The general output characteristics of a pentode is as follows:
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But the idealized output characteristics would look like:
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Thus pentode is a voltage controlled current source.
The incremental model of a pentode is:
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Rp is plate resistance and gm is transconductance and product of the two are amplication factor mu. Amplification factor is the maximum voltage gain that can be obtained from a Common Cathode Pentode Amplifier.