APPLICATION NOTES
MSK 4310 PIN DESCRIPTIONS
V+ -
is the power connection from the hybrid to the
bus. The external wiring to the pin should be sized
according to the RMS current required by the motor.
This pin should be bypassed by a high quality mono-
lithic ceramic capacitor for high frequencies and enough
bulk capacitance to keep the V+ power supply from
drooping.
AØ OUT, BØ OUT, CØ OUT-are
the connections to the
motor phase windings from the bridge output. The wir-
ing to these pins should be sized according to the mo-
tor current requirements. There are no internal short
circuit protection provisions for these output pins in
the hybrid. Shorts to V+ or ground from these pins
must be avoided or the bridge will be destroyed.
GND-
is the power return connection from the hybrid
to the bus. All ground returns internal to the hybrid
connect to this point in a star configuration. All exter-
nal ground connections to this point should be made in
a similar fashion. The V+ capacitors should be returned
to this pin as close as possible. Wire sizing to this pin
connection should be made according to the required
current.
SIG GND -
is the ground pin that connects to the ground
plane for all low power circuitry inside the device.
+15 V INPUT -
is the pin for applying +15 volts to run
the low power control circuitry inside the hybbrid. This
pin should be bypassed to the signal ground pin using
a high quality 10µF tantalum capacitor and a 0.1µF
ceramic capacitor as close to these pins as possible.
-15 V INPUT -
is the pin for applying -15 volts to run
the low power control circuitry inside the hybrid. This
pin should be bypassed to the signal ground pin using
a high quality 10µF tantalum capacitor and a 0.1µF
ceramic capacitor as close to these pins as possible.
BRAKE -
is the pin for commanding the output bridge
into a motor brake mode. When this pin is taken low,
normal operation of the hybrid proceeds. When this
pin is taken high, the three high side switches in the
bridge turn off and the three lowside switches turn
fully on. This will cause rapid deceleration of the motor
and will cease motor operation until taken low again.
The pin left open is internally pulled high.
REF OUT -
is a 6.25 volt regulated output that can be
used to power the hall devices in various motors. Up
to 15 milliamps of current is available.
CURRENT LIMIT ADJUST -
is used to adjust the out-
put current limit. The pin, if left open will limit the
output current to about 1 amp. The pin, taken to ground
will limit the current to about 15 amps. A resistor from
the pin to ground will yield current limits in between.
(See Current Limit Adjust)
SPEED COMMAND (+,-) -
are differential inputs for
controlling the motor speed. With a positive voltage
command the motor will operate in the forward direc-
tion and with a negative command the motor will op-
erate in the reverse direction. The maximum opera-
tional command voltage should be ±5 volts.
HALL A, B & C -
are the hall input pins from the hall
devices in the motor. These pins are internally pulled
up to 6.25 volts. The halls reflect a 120/240 degree
commutation scheme.
TACH RC -
is used to set the tach out pulse width.
This is done by connecting a resistor from this pin to
the REF OUT pin and a capacitor from the pin to the
signal ground. Selection of these components is based
on the desired maximum motor speed. (See TACH RC
component selection)
TACH OUT -
is connected to the -E/A pin through a
resistor when using the speed controller in a closed
loop configuration..
-E/A -
is the error amp inverting input connection. It is
brought out to allow various loop compensation cir-
cuits to be connected between this and E/A out.
E/A OUT -
this is the loop error amp output connec-
tion. It is brought out for allowing various loop com-
pensation circuits to be connected between this and
-E/A.
3
Rev. B
2/04
MSK [ M.S. KENNEDY CORPORATION ]
