mc33931 Freescale Semiconductor, Inc, mc33931 Datasheet - Page 12

• Manufacturer Part Number: mc33931
• Description: 5.0 A Throttle Control H-bridge
• Manufacturer: Freescale Semiconductor, Inc

The device is enabled and fully operational when the EN pin
voltage is logic HIGH. An internal pull-down resistor
maintains the device in Sleep mode in the event EN is driven
through a high-impedance I/O or an unpowered
microcontroller, or the EN/D2 input becomes disconnected.
FEEDBACK (FB)
monitoring of H-bridge high side output currents to facilitate
closed-loop operation for motor speed and torque control.
H-bridge high side drivers. When running in the forward or
reverse direction, a ground-referenced 0.24% of load current
12
33931
FUNCTIONAL DESCRIPTION
FUNCTIONAL PIN DESCRIPTION
The 33931 has a feedback output (FB) for “real time”
The FB pin provides current sensing feedback of the
is output to this pin. Through the use of an external resistor to
ground, the proportional feedback current can be converted
to a proportional voltage equivalent and the controlling
microcontroller can “read” the current proportional voltage
with its analog-to-digital converter (ADC). This is intended to
provide the user with only first-order motor current feedback
for motor torque control. The resistance range for the linear
operation of the FB pin is 100 Ω < R
(only D1), a small filter capacitor (~1.0 µF) may be required
in parallel with the R
suppression.
If PWM-ing is implemented using the disable pin input
FB
Analog Integrated Circuit Device Data
resistor to ground for spike
Freescale Semiconductor
FB
< 300 Ω
.