MC33926 Freescale Semiconductor, MC33926 Datasheet - Page 13

• Manufacturer Part Number: MC33926
• Description: 5.0 A Throttle Control H-Bridge
• Manufacturer: Freescale Semiconductor

device circuitry is fully operational and the supply
I
3, Static Electrical
H-BRIDGE OUTPUT (OUT1, OUT2)
free-wheeling diodes. The bridge output is controlled using
the IN1, IN2, D1, and
current limiting above the I
have thermal shutdown (tri-state latch-OFF) with hysteresis
as well as short circuit latch-OFF protection.
between load currents that are higher than the I
and short circuit currents. This timer is activated at each
output transition.
CHARGE PUMP CAPACITOR (CCP)
the external charge pump reservoir capacitor. The allowable
value is from 30 nF to 100 nF. This capacitor must be
connected from the CCP pin to the VPWR pin. The device
cannot operate properly without the external reservoir
capacitor.
ENABLE INPUT (EN)
as to consume very low currents. When the EN pin voltage is
Analog Integrated Circuit Device Data
Freescale Semiconductor
PWR(STANDBY)
These pins are the outputs of the H-Bridge with integrated
A disable timer (time t
This pin is the charge pump output pin and connection for
The EN pin is used to place the device in a Sleep mode so
current is reduced to a few mA. Refer to
Characteristics,
D2
b
inputs. The outputs have PWM
) is incorporated to distinguish
LIM
threshold. The outputs also
page
7.
LIM
threshold
Table
a logic LOW state, the device is in the Sleep mode. The
device is enabled and fully operational when the EN pin
voltage is logic HIGH. An internal pulldown 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 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
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 < R
(either D1 or
required in parallel with the R
suppression.
The 33926 has a feedback output (FB) for “real time”
The FB pin provides current sensing feedback of the
If PWM-ing is implemented using the disable pin inputs
D2
), a small filter capacitor (~1.0 µF) may be
FUNCTIONAL PIN DESCRIPTION
FB
resistor to ground for spike
FUNCTIONAL DESCRIPTION
FB
< 300
W.
33926
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