3EZ11 Datasheet, PDF (3/5 Pages) Pan Jit International Inc. – GLASS PASSIVATED JUNCTION SILICON ZENER DIODES(VOLTAGE- 11 to 200 Volts Power - 3.0 Watts)

RATING AND CHARACTERISTICS CURVES
3EZ11 THRU 3EZ200
Fig. 2-TYPICAL THERMAL RESPONSE L
Fig. 3-MAXIMUM SURGE POWER
Fig. 4-TYPICAL REVERSE LEAKAGE
APPLICATION NOTE:
Since the actual voltage available from a given zener
diode is temperature dependent, it is necessary to
determine junction temperature under any set of
operating conditions in order to calculate its value. The
following procedure is recommended:
Lead Temperature, T_L, should be determined from:
TL = _LAP_D + T_A
LA ^{is the lead-to-ambient thermal resistance ( /W)}
and P_D is the power dissipation. The value for _LA will
vary and depends on the device mounting method.
LA ^{is generally 30-40 /W for the various chips and}
tie points in common use and for printed circuit board
wiring.
The temperature of the lead can also be measured using
a thermocouple placed on the lead as close as possible
to the tie point. The thermal mass connected to the tie
point is normally large enough so that it will not
significantly respond to heat surges generated in the
diode as a result of pulsed operation once steady-state
conditions are achieved. Using the measured value of
T_L, the junction temperature may be determined by:
T_J = T_L + T_JL
T_JL is the increase in junction temperature above the
lead temperature and may be found from Figure 2 for a
train of power pulses or from Figure 10 for dc power.
T_JL = _LAP_D