UDN2917EB Allegro, UDN2917EB Datasheet - Page 5

• Manufacturer Part Number: UDN2917EB
• Description: Dual Full Bridge PWM Motor Driver 44-Pin PLCC
• Manufacturer: Allegro
• Type: Dual Full Bridge PWM Motor Driverr

Specifications of UDN2917EB

• Package: 44PLCC
• Maximum Operating Current: 105 mA
• Operating Temperature: -20 to 85 °C

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H
H
I
L
L
0
H
H
I
L
L
1
V
V
REF
REF
V
Output Current
REF
/15 R
/30 R
/10 R
0
S
S
= 1/3 I
= 2/3 I
S
= I
TRIP
TRIP
TRIP
current peaks. This peak (appearing across R
comparator, resulting in erroneous current control or high-frequency
oscillations. An external R
the action of the comparator.
winding current at 100%, 67%, 33%, or 0% of the maximum level per
the table. The 0% output current condition turns off all drivers in the
bridge and can be used as an output enable function. These logic level
inputs greatly enhance the implementation of P-controlled drive
formats.
control the motor at a constant torque between all positions in an eight-
step sequence. This is accomplished by digitally selecting 100% drive
current when only one phase is on and 67% drive current when two
phases are on.
current level (and reduced power dissipation) for ‘hold’ conditions
and/or increased current (and available torque) for start-up conditions.
(V
to ground as close as possible to the device. Under no circumstances
should the voltage at LOAD SUPPLY exceed 45 V.
winding current flows. An internally generated deadtime (approxi-
mately 3 s) prevents crossover currents that can occur when switch-
ing the PHASE input.
or I
output clamp and flyback diodes. The fast current decay is desirable
in half-step and high-speed applications. All logic inputs float high; the
ENABLE input must be tied low if it is not used.
of the peak load current for micro-stepping applications, within the
specified limits for V
temperature reaches +170 C. It is only intended to protect the device
from failures due to excessive junction temperature and should not
imply that output short circuits are permitted. The output drivers are
re-enabled when the junction temperature cools to +145 C.
BB
0
Loads with high distributed capacitances may result in high turn-on
Two logic level inputs (I
During half-step operations, the I
The logic control inputs can also be used to select a reduced
To avoid excessive voltage spikes on the LOAD SUPPLY pin
The PHASE input to each bridge determines the direction motor
All four drivers in the bridge output can be turned off (V
Varying the reference voltage (V
Thermal protection circuitry turns off all drivers when the junction
), a large-value capacitor ( 47 F) should be connected from V
= I
1
2.4 V), resulting in a fast current decay through the internal
REF
.
C
0
C
and I
C
low-pass filter may be needed to delay
PWM MOTOR DRIVER
DUAL FULL-BRIDGE
1
) allow digital selection of the motor
0
REF
and I
) provides continuous control
1
inputs allow the P to
S
) will attempt to trip the
EN
2917
2.4 V
BB