MJ16110 Datasheet, PDF (8/10 Pages) Motorola, Inc – POWER TRANSISTORS 15 AMPERES 400 VOLTS 175 AND 135 WATTS

MJ16110 MJW16110
SWITCHMODE DESIGN CONSIDERATIONS (Cont.)
At voltages above 75% of V(BR)CEO(sus), it is essential
to provide the transistor with an adequate amount of base
drive VERY RAPIDLY at turn–on. More specifically, safe op-
eration according to the curves is dependent upon base cur-
rent rise time being less than collector current rise time. As a
general rule, a base drive compliance voltage in excess of
10 volts is required to meet this condition (see Application
Note AN875).
TURN–OFF
A bipolar transistor’s ability to withstand turn–off stress is
dependent upon its forward base drive. Gross overdrive vio-
lates the RBSOA curve and risks transistor failure. For this
reason, circuits which use fixed base drive are more likely to
fail at light loads due to heavy overdrive (see Application
Note AN875).
OPERATION ABOVE V(BR)CEO(sus)
When bipolars are operated above collector–emitter
breakdown, base drive is crucial. A rapid application of ade-
quate forward base current is needed for safe turn–on, as is
a stiff negative bias needed for safe turn–off. Any hiccup in
the base–drive circuitry that even momentarily violates either
of these conditions will likely cause the transistor to fail.
Therefore, it is important to design the driver so that its out-
put is negative in the absence of anything but a clean crisp
input signal (see Application Note AN952).
RBSOA
Reversed Biased Safe Operating Area has a first order
dependency on circuit configuration and drive parameters.
The RBSOA curves in this data sheet are valid only for the
conditions specified. For a comparison of RBSOA results in
several types of circuits (see Application Note AN951).
DESIGN SAMPLES
Transistor parameters tend to vary much more from wafer
lot to wafer lot, over long periods of time, than from one de-
vice to the next in the same wafer lot. For design evaluation
it is advisable to use transistors from several different date
codes.
BAKER CLAMPS
Many unanticipated pitfalls can be avoided by using Baker
Clamps. MUR105 and MUR170 diodes are recommended
for base drives less than 1 amp. Similarly, MUR405 and
MUR470 types are well–suited for higher drive requirements
(see Article Reprint AR131).
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Motorola Bipolar Power Transistor Device Data