UDQ2916 Allegro MicroSystems, Inc., UDQ2916 Datasheet - Page 6

• Manufacturer Part Number: UDQ2916
• Description: Udn2916 Udq2916 Dual Full-bridge Pwm Motor Driver
• Manufacturer: Allegro MicroSystems, Inc.

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 microprocessor
controlled drive formats.
control the motor at a constant torque between all positions in an eight-step se-
2916
FROM
Two logic level inputs (I
During half-step operations, the I
μP
56 kΩ
R
l
H
H
L
L
T
0
V
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
0
I
H
H
L
L
1
and I
1
1
) allow digital selection of the motor
V
BB
0
and I
V
CC
θ
1
24
19
18
23
22
21
20
17
16
13
15
14
1
allow the microprocessor to
V
V
R
REF
C
REF
V
+5 V
REF
Output Current
/30 R
/15 R
R
V
C
S
REF
/10 R
C
S
S
FROM
μP
820 pF
0
C
T
= 2/3 I
= 1/3 I
S
= I
TRIP
Dwg. EP-008B1
56 kΩ
STEPPER
MOTOR
R
TRIP
TRIP
T
+
V
Dual Full-Bridge Motor Driver
BB
quence. 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 I
rapid current decay when switching phases. This
helps to ensure proper motor operation at high step
rates.
select a reduced current level (and reduced power
dissipation) for "hold" conditions and/or increased
current (and available torque) for start-up condi-
tions.
GENERAL
the direction motor winding current fl ows. An in-
ternally generated dead time (approximately 2 μs)
prevents crossover currents that can occur when
switching the PHASE input.
turned-off between steps (I
ing in a fast current decay through the internal
output clamp and fl yback diodes. The fast current
decay is desirable in half-step and high-speed ap-
plications. The PHASE, I
vides continuous control of the peak load current
for micro-stepping applications.
drivers when the junction temperature reaches
+170°C. It is only intended to protect the device
from failures due to excessive junction tempera-
ture and should not imply that output short circuits
are permitted. The output drivers are re-enabled
when the junction temperature cools to +145°C.
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 ex-
cellent thermal properties of the package designs,
this allows continuous operation of both bridges
simultaneously at 500 mA.
PHASE
The logic control inputs can also be used to
The PHASE input to each bridge determines
All four drivers in the bridge output can be
Varying the reference voltage, V
Thermal protection circuitry turns-off all
The UDx2916 output drivers are optimized
H
L
115 Northeast Cutoff, Box 15036
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 (508) 853-
5000
www.allegromicro.com
TRUTH TABLE
0
and I
OUT
1
H
L
turn-off all drivers to allow
A
0
,and I
0
= I
1
1
≥ 2.4 V), result-
inputs fl oat high.
OUT
REF
H
L
B
, pro-
6