MSK4227S Datasheet, PDF (3/4 Pages) M.S. Kennedy Corporation – 200 VOLT 20 AMP MOSFET H-BRIDGE WITH GATE DRIVE GATE DRIVE

APPLICATION NOTES
MSK 4227 PIN DESCRIPTIONS
+VCC - Is the low voltage supply for all the internal logic and
drivers. A 0.1µF ceramic capacitor in parallel with a 10µF
tantalum capacitor is the recommended bypassing from the
+VCC pin to the COM pin.
HINA, HINB - Are high active logic inputs for signaling the
corresponding phase high-side switch to turn on. The logic
inputs are compatible with standard CMOS or LSTTL outputs.
These logic numbers are internally zener clamped at 5.2 volts.
LINA, LINB - Are low active logic inputs for signaling the cor-
responding phase low-side switch to turn on. The logic in-
puts are compatible with standard CMOS or LSTTL outputs.
These logic numbers are internally zener clamped at 5.2 volts.
AØ, BØ - Are the pins connecting the 3 phase bridge switch
options.
AV-, BV- - Are the connections from the bottoms of the three
half bridges. These pins get connected to the COM pin. If
current sensing is desired they may be connected to the COM
pin through a low value sense resistor.
+VB - Is the connection used to provide power to the floating
high-side bootstrap supplies in the gate drive circuitry.
V+ - Is the high voltage positive rail connection to the tops of
the three half bridges. Proper power supply bypassing must
be connected from this pin to the COM pin for good filtering.
This bypassing must be done as close to the hybrid as pos-
sible.
COM - Is the connection that all hybrid power supply connec-
tions are returned to and bypassed to.
TYPICAL SYSTEM OPERATION
IN ^{This is a diagram of a typical application of the MSK4227.}
The design +Vcc voltage is +15 volts and should have a
good low ESR bypass capacitor such as a tantalum electro-
lytic. The digital inputs can come from a microprocessor or
any type of PWM controller. The controller will use the cur-
rent sense signal to either control current through PWM, cur-
rent limit the bridge, or both.
Current sensing is done in this case by a 0.1 ohm sense
resistor to sense current from both legs of the bridge sepa-
rately. It is important to make the high current traces as big as
possible to keep inductance down. The storage capacitor con-
nected to the V+ and the module should be large enough to
provide the high energy pulse without the voltage sagging
too far. A low ESR ceramic capacitor or large polypropylene
capacitor will be required. Mount the capacitor as close to the
module as possible. The connection between GND and the
V+ return should not be carrying any motor current. The
sense resistor signal is common mode filtered as necessary to
feed the limiting circuitry for the microprocessor. This appli-
cation will allow full four quadrant torque control for a closed
loop servo system. Any modulation scheme may be used,
however, but the current sensing scheme may have to change.
A snubber network is usually required, due to the induc-
tance in the power loop. It is important to design the snubber
network to suppress any positive spikes above 200V and
negative spikes below -2V with respect to ground.
3
Rev. B 11/04