APPLICATION NOTES

MSK 4400 PINOUT DESCRIPTIONS

3

Rev. E 6/01

AØ, BØ, CØ - Are the connections to the motor phase

windings from the bridge output. The wiring to these pins

should be sized according to the required current by the

motor. There are no short circuit provisions for these out-

puts. Shorts to V+ or gound from these pins must be

avoided or the bridge will be destroyed.

AL, BL, CL - Are the logic level inputs for controlling the

low side switch for each of the three phases. A logic

HIGH turns the low side output on, sinking the output cur-

rent and pulling it down. If the corresponding high side

switch is ON, the device will turn off the high side output,

insert the dead time and then command the lowside out-

put on. The low side input has priority over the high side

input.

AH, BH, CH - Are the logic level inputs for controlling the

high side switch for each of the three phases. A logic low

turns the high side output ON, sourcing the output current

and pulling it up. If the corresponding low side switch is

ON, the device will ignore the high side input until the

lowside is turned off and dead time has elapsed. Again,

the lowside input has priority.

AV+,BV+,CV+ - Are the power connections from the

hybrid 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

test circuit. The voltage range on these pins is from 16

volts up to 75 volts.

three phase bridge. A low value resistor between here

and the GND will produce a voltage proportional to cur-

rent in the bridge. Both pins must be connected. If a resis-

tor is not used, these pins must be connected to GND.

EN - Is the logic level input for enabling and disabling the

bridge outputs. A logic low enables output switching.

GND - Is the logic input return connection, the VBIAS

return and the V+ return.

SWR - Is the control for the amount of dead time be-

tween a high side switch ON and the corresponding low

side switch OFF and vice versa. Leaving it open creates

the most dead time, while connecting a 12 K resistor to

VBIAS creates the least.

VBIAS - Is the supply voltage for running all of the low

level logic and gate drive functions.This pin should be by-

4.7µF bulk capacitor.