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3932

THREE-PHASE POWER MOSFET CONTROLLER

Pin Descriptions

pulled up to LCAP. Logic HIGH will disable the device and

turn off MOSFETs, coasting the motor. Logic LOW will

enable gate drive to follow commutation logic. This input

will override BRAKE.

MOSFET drivers. External series gate resistors can be used

to control slew rate seen at the power driver gate, thereby

controlling the di/dt and dv/dt of S outputs. The outputs will

source 1.25A for turn-on and sink 2.5A for gate discharge.

these pins sense the voltages switched across the load. The

pin is also connected to the negative side of the bootstrap

capacitor and negative supply connection for the floating

high side drive.

channel MOSFET drivers. External series gate resistors can

be used to control slew rate seen at the power driver gate,

thereby controlling the di/dt and dv/dt of S outputs. The

outputs will source 1.25A for turn-on and sink 2.5A for gate

discharge.

positive supply for high side gate drive. The bootstrap

capacitor is charged to approximately VREG when the

output Sx terminal is low. When the output swings high, the

voltage on this pin rises with the output to provide the

boosted gate voltage needed for N-channel power

MOSFETs.

decay mode (logic HIGH) switches off the high side FET in

response to PWM Off command. Fast decay mode (logic

LOW) switches off the source and sink MOSFET’s. Mode

pin is internally pulled up to LCAP.

LCAP. Configured for 120-degree electrical spacing.

table. Internally pulled up to LCAP.

go active high for any of the following fault conditions:

1)

Invalid HALL input code.

2)

High side gate-source undervoltage.

3)

Bootstrap capacitor not sufficiently charged.

4)

Undervoltage condition detected at VREG.

5)

Thermal Shutdown.

6)

Motor lead (SA/SB/SC) connected to ground.

Any fault will force a COAST condition, which turns all

power MOSFETs off. The fault state for gate-source and

bootstrap monitors is cleared at each commutation. If the

motor has stalled, the fault must be cleared by toggling the

RESET pin or repeating a power up sequence.

turn on sink side MOSFETs, turn off the source side

MOSFETs. This will effectively short the BEMF in the

windings and brake the motor. Internally pulled up to logic

LCAP.

the feature forcing current decay through flyback diodes.

Logic HIGH will result in the opposite pair of drivers to

switch in response to a PWM “off” command. Internally

pulled up to LCAP.

pulse appears at every Hall transition.

MOSFETs selected by Hall input logic. Logic LOW turns

off the selected MOSFETs. The PWM input held high to

utilize internal current control circuitry. Internally pulled up

to logic LCAP.

applications information). It is recommended that the fixed

off time should not be less than 10

µs. The resistor should be

in the range 10k to 500k.

Voltage representing load current appears on this pin.

Voltage transients seen at this pin when the drivers turn on