APPLICATION NOTES
MSK 4900 PIN DESCRIPTIONS
VCC -
is the bias supply voltage for supplying the input logic
and the power supply for the isolated output. This pin should
be bypassed to GND with a 4.7µF tantalum capacitor and a
0.1µF ceramic capacitor as close this pin and GND as pos-
sible.
X OFF -
is the gate drive output pin for turning the gate off.
This pin will sink TBD current. A separate gate resistor shall
be selected to tailor the turn-off characteristics. This pin will
turn off to -5V.
GND -
is the Vcc supply return for the input logic and the
internal isolated supply. This GND is completely isolated from
the output section. No output returns should connect to this
GND in order to preserve isolation. All Vcc bias supply by-
pass connections should be made as close to this pin as pos-
sible. An input ground plane is the most preferred layout for
assuring good, low impedance ground, shielding of inputs
from noise, etc.
DE-SAT SENSE X -
is the input connection for sensing de-
saturation. This pin shall be connected to the collector of the
IGBT. This pin is blanked during switching so that it will not
false trip.
X VDD -
is the pin for the floating gate supply voltage. TBD
capacitance shall be connected between this pin and X VSS
as close to the pin as possible. Nominally, this voltage will be
+15V with respect to the RETURN X pin and the emitter of
the IGBT.
HI -
is the input logic pin for commanding the high-side gate
drive to turn on. This logic input is TTL compatible. This in-
put is exclusive OR'd with LO to protect against simultaneous
turn on of both the high-side and low-side gate drive.
X VSS -
is the return pin for the floating gate supply voltage.
TBD capacitance shall be connected between this pin and X
VDD as close to the pins as possible. Nominally, this voltage
will be -5V with respect to the RETURN X pin and the emitter.
LO -
is the input logic pin for commanding the low-side gate
drive to turn on. This logic input is TTL compatible. This in-
put is exclusive OR'd with HI to protect against simultaneous
turn on of both the high-side and low-side gate drive.
X FAULT -
is an open collector output for indicating either a
de-saturation condition or an undervoltage condition for the
gate drive. This output will be cleared upon activation of
X FAULT CLEAR.
SS X -
is the soft shutdown pin for slowly turning the gate
off after a de-saturation condition. This pin is a separate gate
turn-off path and requires a separate gate resistor for this spe-
cial turn-off approach. The resistor should be sized to keep di/
dt from being too high after the de-sat condition.
IN
RETURN X -
is the pin for the emitter reference. This pin will
be at zero volts to +15V to -5V for the gate drive voltage.
X FAULT CLEAR -
is a logic input pin for clearing a FAULT
condition. This input should not be activated until shutdown
of the affected gate is complete. Allow (TBD) µSec after FAULT
before activation of this pin.
X ON -
is the gate drive output pin for turning the gate on.
This pin will source TBD current. A separate gate resistor shall
be selected to tailor the turn-on characteristics. This pin will
turn on to +15V.
NOTE: X = HI or LO
3
PRELIMINARY
Rev. - 1/07
MSK [ M.S. KENNEDY CORPORATION ]
