APPLICATION NOTES

IN

MSK 4253 PIN DESCRIPTIONS

AV+, BV+ - are the power connections from the hybrid to

the bus. All pins for the motor voltage supply should be con-

nected together to share the current through the pins in the

hybrid.

The external wiring to these pins should be sized

according to the RMS current required by the motor. A high

quality monolithic ceramic capacitor for high frequencies and

enough bulk capacitance for keeping the V+ supply from

drooping should bypass these pins. 100µF minimum is rec-

ommended. Capacitors should be placed as close to these

pins as practical. The addition of high quality ceramic capaci-

tance will help with noise issues.

OUTPUT A, OUTPUT B- 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.

RTN - is the power return connection from the module to the

bus. All internal ground returns connect to this point inside

the hybrid. All capacitors from the V+ bus should connect to

this point as close as possible. All external V+ return con-

nections should be made as close to these pins as possible.

Wiring sizing to this pin should be made according to the

required current.

GND - is the return point for the low powered circuitry inside

the hybrid. All GND pins should be tied together. All capaci-

tors for bypassing the + and -15V supplies should be tied at

this point, as close to the pins as possible. Any ground plane

connections for low powered and analog citcuitry outside the

hybrid should be tied to this point.

+15VIN - is the input for applying +15 volts to run the low

power section of the hybrid. Both pins should be used to-

gether for optimum operation. These pins should be bypassed

with a 10µF capacitor and a 0.1µF capacitor as close to these

pins as possible.

-15VIN - is the input for applying -15 volts to run the low

power section of the hybrid. Both pins should be used to-

gether for optimum operation. These pins should be bypassed

with a 10µF capacitor and a 0.1µF capacitor as close to these

pins as possible.

SENSE RESISTOR + - is the top of the sense resistor for

sensing the bridge current and closing the loop. The bottom

of the sense resistor is RTN. All RSENSE A and RSENSE B

pins should be connected to this point, with connectios being

as short as possible.

RSENSE A, RSENSE B - are the power pins for the bottom

of the bridge. Both of these pins are to be connected to sense

resistor +, with connections being as short as possible.

DIS - is a pin for externally disabling the output bridge. A TTL

logic low will enable the bridge and a TTL high will disable it.

It is internally pulled up by a 100µAmp pull-up.

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 direc-

tion. The maximum operational command voltage should be

±5 volts for ±5 amps of motor current. Going beyond 5

volts of command voltage will force the bridge to conduct

more than the desired maximum current. There is internal

current limiting that will ultimately limit the absolute maximum

current being output by the bridge. The input impedance is

approximately 3.75K

Ω for each pin.

CURRENT MONITOR - is a pin providing a current viewing

signal for external monitoring purposes. This is scaled at ±1

amp of motor current per volt output, up to a maximum of ±5

volts, or ±5 amps. Going beyond the 5 volt maximum may

result in clipping of the waveform peaks.

E/A OUT - is the current loop error amplifier output.

It is

brought out for allowing various loop compensation circuits

to be connected between this and E/A-.

E/A- - is the current loop error amplifier inverting input. It is

brought out for allowing various loop compensation circuits

to be connected between this and E/A OUT.

3

PRELIMINARY

Rev. - 2/05