UDQ2916B-T ALLEGRO [Allegro MicroSystems], UDQ2916B-T Datasheet - Page 6

• Manufacturer Part Number: UDQ2916B-T
• Description: DUAL FULL-BRIDGE PWM MOTOR DRIVER
• Manufacturer: ALLEGRO [Allegro MicroSystems]

LOGIC CONTROL OF OUTPUT CURRENT
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
µP-controlled drive formats.
motor at a constant torque between all positions in an eight-step
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FROM
Two logic level inputs (l
During half-step operations, the l
µP
56 kΩ
R
l
H
H
L
L
V
T
0
REF
R
S
C
C
820 pF
C
CURRENT-CONTROL TRUTH TABLE
R
T
C
12
10
11
8
9
1
2
3
4
5
6
7
9
θ
TYPICAL APPLICATION
2
2
H
0
L
H
I
L
1
and I
1
1
V
) allow digital selection of the motor
BB
0
V
CC
θ
and l
1
24
19
18
23
22
21
20
17
16
13
15
14
1
allow the µP to control the
R
C
V
V
REF
REF
+5 V
V
Output Current
REF
R
/30 R
/15 R
V
C
S
REF
C
/10 R
FROM
µP
820 pF
S
C
S
0
T
= 2/3 I
= 1/3 I
S
= I
56 k Ω
TRIP
Dwg. EP-008B1
STEPPER
MOTOR
R
TRIP
TRIP
T
+
V
BB
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. Logic highs on both l
turn OFF all drivers to allow rapid current
decay when switching phases. This helps to
ensure proper motor operation at high step
rates.
used to select a reduced current level (and
reduced power dissipation) for ‘hold’ condi-
tions and/or increased current (and available
torque) for start-up conditions.
GENERAL
determines the direction motor winding
current ows. An internally generated
deadtime (approximately 2 µs) prevents
crossover currents that can occur when
switching the PHASE input.
be turned OFF between steps (l
resulting
internal output clamp and yback diodes. The
fast current decay is desirable in half-step and
high-speed applications. The PHASE, l
inputs oat high.
provides continuous control of the peak load
current for micro-stepping applications.
all drivers when the junction 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.
are optimized for low output saturation
voltages—less than 1.8 V total (source plus
sink) at 500 mA. Under normal operating
conditions, when combined with the excellent
thermal properties of the batwing package
design, this allows continuous operation of
both bridges simultaneously at 500 mA.
The logic control inputs can also be
The PHASE input to each bridge
All four drivers in the bridge output can
Varying the reference voltage (V
Thermal protection circuitry turns OFF
The UDN2916B/EB/LB output drivers
DUAL FULL-BRIDGE
in a fast current decay through the
MOTOR DRIVER
0
= l
1
0
≥2.4 V)
2916
REF
and l
0
, and I
)
1
1
6