TM 11-6625-539-15-2
TRANSISTOR CHARACTERISTIC DATA FOR
TEST SET, TRANSISTOR TS-183613/U
the ICO parameter if it does not contain a leakage cur-
Two of the most important parameters for testing
rent. A plot of collector current versus collector volt-
transistors in circuit are Ico and beta. Minimum value
age of a reverse-biased collector-to-base junction with
of beta and maximum values of Ico are presented as
a negligible amount of leakage current yields a graph
an aid in determining faulty transistor and tran-
which rises to some current rather quickly and then
sistors that have started to degrade.
remains constant with increasing voltage until the
Beta is normally specified by the manufacturer at
breakdown voltage of the junction is reached. A leak-
various collector-to-emitter voltages; however, beta
age component across the junction modifies this curve
is normally independent of collector-to-emitter volt-
age above the saturation voltage. The magnitude of
in an amount depending on the amount of leakage
the beta of a transistor, therefore, measured at a
present across the junction. The figure of 6 volts was
potential slightly above the saturation voltage is
chosen as one that would give maximum information
very close to the magnitude of the beta measured at
on the largest amount of transistors and diodes. A
some higher potential. The appendix shows data
device with a lower breakdown voltage than 6 volts
gathered from manufacture and specification
will not be damaged since the power, when this meas-
sheets which accounts for the various .
potentials for
which beta is given. The same reasoning is true for
urement is made, is limited to less than 5 milliwatts.
