APPLICATION NOTES
MSK 4370 PIN DESCRIPTIONS
AV+, BV+, CV+ -
are the power connections from the hy-
brid to the bus. The pins for each phase are brought out
separately and must be connected together to the V+ source
externally. The external wiring to these pins should be sized
according to the RMS current required by the motor. These
pins should be bypassed by a high quality monolithic ceramic
capacitor for high frequencies and enough bulk capacitance
for keeping the V+ supply from drooping.
AØ, BØ & CØ-
are the connections to the motor phase wind-
ings from the bridge output. The wiring to these pins should
be sized according to the current required by the motor. There
are no short circuit provisions for these outputs. Shorts to
V+ or ground from these pins must be avoided or the bridge
will be destroyed.
AVS, BVS, CVS -
are the return pins on the bottom of each
half bridge. They are brought out separately and should be
connected together externally to allow the current from each
half bridge to flow through the sense resistor. The wiring on
these pins should be sized according to the current require-
ments of the motor.
RTN -
is the power return connection from the module to the
bus. All ground returns connect to this point from internal to
the module in a star fashion. All external ground connections
to this point should also 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.
LGND -
is an isolated ground connection to the RTN pin of
the hybrid that is connected internally. For any circuitry that
needs to be connected to the RTN pin without the influence
of current flow through RTN should be connected at this
point.
GND -
is a ground pin that connects to the ground plane for
all low powered circuitry inside the hybrid.
+15 VIN -
is the input for applying +15 volts to run the low
power section of the hybrid. This pin should be bypassed
with a 10 µF capacitor and a 0.1 µF capacitor as close to this
pin as possible.
-15 VIN -
is the input for applying -15 volts to run the low
power section of the hybrid. This pin should be bypassed
with a 10 µF capacitor and a 0.1 µF capacitor as close to this
pin as possible.
CURRENT COMMAND (+,-) -
are differential inputs for con-
trolling the module in current mode. Scaled at ±1 amp per
volt of input command, the bipolar input allows both forward
and reverse current control capability regardless of motor com-
mutation direction. The maximum operational command volt-
age should be ±10 volts for ±10 amps of motor current.
CURRENT MONITOR-
is a pin providing a current viewing sig-
nal for external monitoring purposes. This is scaled at ±1
amp of motor current per volt output, up to a maximum of
±10 volts, or ±10 amps. As ±10 amps is exceeded, the
peaks of the waveform may become clipped as the rails of
the amplifiers are reached. This voltage is typically ±12.5
volts, equating to ±12.5 amps of current peaks.
3
Rev. B 5/02
E/A OUT -
is the current loop error amp output connection.
It is brought out for allowing various loop compensation cir-
cuits to be connected between this and E/A-.
E/A- -is
the current loop error amp inverting input connec-
tion. It is brought out for allowing various loop compensa-
tion circuits to be connected between this and E/A OUT.
CLOCK SYNC-
is an input for synchronizing to an external
clock. The sync circuit will trigger on the edges of the ap-
plied clock and effectively shorten the period of the internal
oscillator on each cycle. The frequency can be increased
from a free running 22 KHz to 25 KHz maximum. The clock
applied shall be 15 volts amplitude with at least a 10% duty
cycle.
REFOUT -
is a 6.25 volt regulated output to be used for pow-
ering the hall devices in various motors. Up to 15 mA of
output current is available.
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 can reflect a 120/240 degree commutation
scheme or a 60/300 degree scheme.
BRAKE -
is a pin for commanding the output bridge into a
motor BRAKE mode. When pulled low, normal operation com-
mences. When pulled high, the 3 high side bridge switches
turn off and the 3 low side bridge switches turn on, causing
rapid deceleration of the motor and will cease motor opera-
tion until pulled high again. Logic levels for this input are TTL
compatible. It is internally pulled high.
DIS -
is a pin for externally disabling the output bridge. A
TTL logic low will enable the bridge and a TTL logic high will
disable it. It is internally pulled up by a 150 µAmp pullup.
60/120-
is a pin fpr selecting the orientation of the commuta-
tion sheme of the motor. A high state will produce 60/300
degree commutation, whereas a low state will produce 120/
240 degree commutation. Logic levels for this input are TTL
compatible. It is internally pulled high.
IN
MSK [ M.S. KENNEDY CORPORATION ]
