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A New Junction Transistor High-Frequency Equivalent Circuit

Middlebrook, R. D. (1957) A New Junction Transistor High-Frequency Equivalent Circuit. Caltech Antenna Laboratory Technical Report, 9. California Institute of Technology , Pasadena, CA. (Unpublished)

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A small-signal equivalent circuit for a junction transistor is presented which is applicable to alloy or grown types of p-n-p or n-p-n transistors, and which is valid from d-c up to twice the cutoff frequency. The equivalent circuit is in the form of four short-circuit admittances, each of which can be represented by a simple network of lumped elements constant with frequency. The derivation is based on physical principles and takes into account base widening and collector barrier capacitance. Equations for the equivalent circuit element values are given either in terms of physical parameters or in terms of six practical measurements. The four-admittance representation is given both for common-emitter and common-base connections, and a relation between the common- emitter and the common-base cutoff frequencies is derived and experimentally verified. Measurements of the real and imaginary parts of the four admittances as functions of frequency for several transistors show excellent agreement with the values predicted by the equivalent circuit.

Item Type:Report or Paper (Technical Report)
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Additional Information:This work was performed in part at Stanford University under Office of Naval Research Contract N6onr 251(07) (NR 373 360). The author wishes to thank Dr. J. M. Pettit, Dr. G. S. Bahrs, Dr. R. M. Scarlett, and K. G. Sorenson, all of Stanford University, for valuable assistance and discussion. The work was completed at the California Institute of Technology under Air Force Office of Scientific Research Contract AF 18(600)-1113. The numerical values in Table I were obtained by R. L. Walker at the Stanford Electronics Laboratories, and are part of a larger series of measurements used by him to verify a rather more accurate expression for the cutoff frequency of the common-base practical transistor than that given in (111). Figures 7 through 10 are reproduced by kind permission of John Wiley and Sons, Inc.
Group:Caltech Antenna Laboratory
Funding AgencyGrant Number
Air Force Office of Scientific Research (AFOSR)AF 18(600)-1113
Office of Naval Research (ONR)NR 373 360
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Other Numbering System NameOther Numbering System ID
ASTIAAD 120 469
Series Name:Caltech Antenna Laboratory Technical Report
Issue or Number:9
Record Number:CaltechAUTHORS:20190923-144144455
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:98804
Deposited By: Melissa Ray
Deposited On:23 Sep 2019 22:09
Last Modified:03 Oct 2019 21:44

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