A3989
Bipolar Stepper and High Current DC Motor Driver
Last Time Buy
This part is in production but has been determined to be
LAST TIME BUY. This classification indicates that the product is
obsolete and notice has been given. Sale of this device is currently
restricted to existing customer applications. The device should not be
purchased for new design applications because of obsolescence in the
near future. Samples are no longer available.
Date of status change: September 3, 2018
Deadline for receipt of LAST TIME BUY orders: June 30, 2019
and for new customers or new applications, refer to the
A5989GEVTR-T.
Recommended Substitutions:
For existing customer transition,
NOTE: For detailed information on purchasing options, contact your
local Allegro field applications engineer or sales representative.
Allegro MicroSystems, Inc. reserves the right to make, from time to time, revisions to the anticipated product life cycle plan
for a product to accommodate changes in production capabilities, alternative product availabilities, or market demand. The
information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no respon-
sibility for its use; nor for any infringements of patents or other rights of third parties which may result from its use.
A3989
Bipolar Stepper and High Current DC Motor Driver
FEATURES AND BENEFITS
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36 V output rating
2.4 A DC motor driver
1.2 A bipolar stepper driver
Synchronous rectification
Internal undervoltage lockout (UVLO)
Thermal shutdown circuitry
Crossover-current protection
Very thin profile QFN package
DESCRIPTION
The A3989 is designed operate at voltages up to 36 V while driving
one bipolar stepper motor at currents up to 1.2A, and one DC motor
at currents up to 2.4 A. The A3989 includes a fixed off-time pulse-
width modulation (PWM) regulator for current control. The stepper
motor driver features dual 2-bit nonlinear DACs (digital-to-analog
converters) that enable control in full, half, and quarter steps. The
DC motor is controlled using standard PHASE and ENABLE signals.
Fast or slow current decay is selected via the MODE pin. The PWM
current regulator uses the Allegro
™
patented mixed decay mode for
reduced audible motor noise, increased step accuracy, and reduced
power dissipation.
Internal synchronous rectification control circuitry is provided to
improve power dissipation during PWM operation.
Protection features include thermal shutdown with hysteresis,
undervoltage lockout (UVLO) and crossover current protection.
Special power up sequencing is not required.
The A3989 is supplied in a leadless 6 mm × 6 mm × 0.9 mm, 36-pin QFN
package with exposed power tab for enhanced thermal performance.
The package is lead (Pb) free, with 100% matte tin leadframe plating.
Package: 36 pin QFN with exposed thermal pad
0.90 mm nominal height (suffix EV)
Not to scale
0.1 µF
50 V
CP1
VDD
0.1 µF
50 V
CP2
VCP
VBB
VBB
OUT1A
OUT1B
100 µF
50 V
0.22 µF
50 V
PHASE1
I01
Microcontroller or
Controller Logic
I11
PHASE2
I02
I12
PHASE3
ENABLE
MODE
VREF1
VREF2
VREF3
A3989
SENSE1
OUT2A
OUT2B
SENSE2
OUT3A
OUT3A
OUT3B
OUT3B
SENSE3
GND
GND
SENSE3
Figure 1. Typical application circuit
A3989DS, Rev. 5
MCO-0000354
September 10, 2018
A3989
SELECTION GUIDE
Part Number
A3989SEV-T
A3989SEVTR-T
Bipolar Stepper and High Current DC Motor Driver
Packing
61 pieces per tube
1500 pieces per reel
ABSOLUTE MAXIMUM RATINGS
Characteristic
Load Supply Voltage
Logic Supply Voltage
Symbol
V
BB
V
DD
Stepper motor driver, continuous
Output Current
*
I
OUT
Stepper motor driver, pulsed t
w
< 1 µs
Dc motor driver, continuous
Dc motor driver, pulsed t
w
< 1 µs
Logic Input Voltage Range
SENSEx Pin Voltage
VREFx Pin Voltage
Operating Temperature Range
Junction Temperature
Storage Temperature Range
V
IN
V
SENSEx
V
REFx
T
A
T
J
(max)
T
stg
Range S
Pulsed t
w
< 1 µs
Pulsed t
w
< 1 µs
Notes
Rating
–0.5 to 36
38
–0.4 to 7
1.2
2.8
2.4
3.5
–0.3 to 7
0.5
2.5
2.5
–20 to 85
150
–55 to 150
Units
V
V
V
A
A
A
A
V
V
V
V
°C
°C
°C
* May be limited by duty cycle, ambient temperature, and heat sinking. Under any set of conditions, do not exceed the specified current rating or a
Junction Temperature of 150°C.
THERMAL CHARACTERISTICS:
May require derating at maximum conditions
Characteristic
Package Thermal Resistance
Symbol
R
θJA
Test Conditions
EV package, 4 layer PCB based on JEDEC standard
Power Dissipation versus Ambient Temperature
5500
5000
4500
4000
Min.
27
Units
°C/W
Power Dissipation, P
D
(mW)
3500
3000
2500
2000
1500
1000
500
0
25
50
75
100
125
Temperature (°C)
150
175
EV Package
4-layer PCB
(R
θJA
= 27 ºC/W)
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
2
A3989
Bipolar Stepper and High Current DC Motor Driver
Functional Block Diagram
0.1 µF
50 V
0.1 µF
50 V
100 µF
50 V
0.22 µF
50 V
To
V
BB2
VCP
VBB
VBB
CP1
CP2
VDD
DMOS
Full Bridge 1
VBB1
OSC
CHARGE PUMP
V
CP
OUT1A
PHASE1
I01
I11
PHASE2
I02
I12
Sense1
VREF1
3
OUT1B
Control Logic
Stepper Motor
GATE
DRIVE
SENSE1
VBB1
R
S1
DMOS
Full Bridge 2
-
PWM Latch
BLANKING
+
OUT2A
VREF2
3
Sense 2
+
-
PWM Latch
BLANKING
V
CP
OUT2B
PHASE3
ENABLE
MODE
Control Logic
DC Motor
Sense 2
Sense 3
SENSE2
R
S2
OUT3A
OUT3A
GATE
DRIVE
Sense 3
VREF3
3
+
PWM Latch
BLANKING
DMOS
Full Bridge 3
OUT3B
OUT3B
SENSE3
SENSE3
-
R
S3
GND
GND
NC
NC
NC
NC
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
3
A3989
Characteristics
Bipolar Stepper and High Current DC Motor Driver
Symbol
V
BB
V
DD
I
DD
R
DS(on)DC
R
DS(on)st
I
DSS
I
BB
V
IN(1)
V
IN(0)
I
IN
V
hys
PWM change to source on
t
pd
t
COD
t
BLANKdc
t
BLANKst
V
REFx
I
REF
V
ERR
Operating
V
REF
= 1.5
V
REF
= 1.5, phase current = 100%
V
REF
= 1.5, phase current = 67%
V
REF
= 1.5, phase current = 33%
V
UV(VBB)
V
UV(VBB)hys
V
UV(VDD)
V
UV(VDD)hys
T
JTSD
T
JTSDhys
V
DD
rising
V
BB
rising
PWM change to source off
PWM change to sink on
PWM change to sink off
V
IN
= 0 to 5 V
Sink driver, I
OUT
= 1.2 A, TJ = 25°C
Sink driver, I
OUT
= 1.2 A, TJ = 25°C
I
OUT
= 1.2 A
Outputs, V
OUT
= 0 to V
BB
I
OUT
= 0 mA, outputs on, PWM = 50 kHz,
DC = 50%
Source driver, I
OUT
= –1.2 A, TJ = 25°C
Source driver, I
OUT
= –1.2 A, TJ = 25°C
Test Conditions
Min.
8.0
3.0
–
–
–
–
–
–
–20
–
0.7×V
DD
–
–20
150
350
35
350
35
300
2.5
0.7
0.0
–
–5
–5
–15
7.3
400
2.65
75
155
–
Typ.
[2]
–
–
7
350
350
700
700
–
–
–
–
–
<1.0
300
550
–
550
–
425
3.2
1
–
–
–
–
–
7.6
500
2.8
105
165
15
Max.
36
5.5
10
450
450
800
800
1.3
20
8
–
0.3×V
DD
20
500
1000
300
1000
250
1000
4
1.3
1.5
±1
5
5
15
7.9
600
2.95
125
175
–
Units
V
V
mA
mΩ
mΩ
mΩ
mΩ
V
µA
mA
V
V
µA
mV
ns
ns
ns
ns
ns
µs
µs
V
μA
%
%
%
V
mV
V
mV
°C
°C
ELECTRICAL CHARACTERISTICS
[1]
: Valid at T
A
= 25 °C, V
BB
= 36 V, unless otherwise noted
Load Supply Voltage Range
Logic Supply Voltage Range
VDD Supply Current
Output On Resistance (DC motor driver)
Output On Resistance (stepper motor
driver)
V
f
, Outputs
Output Leakage
VBB Supply Current
CONTROL LOGIC
Logic Input Voltage
Logic Input Current
Input Hysteresis
Propagation Delay Times
Crossover Delay
Blank Time (DC motor driver)
Blank Time (stepper motor driver)
VREFx Pin Input Voltage Range
VREFx Pin Reference Input Current
Current Trip-Level Error
[3]
PROTECTION CIRCUITS
VBB UVLO Threshold
VBB Hysteresis
VDD UVLO Threshold
VDD Hysteresis
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
[1]
For
[2]
Typical
Operating
Operating
input and output current specifications, negative current is defined as coming out of (sourcing) the specified device pin.
data are for initial design estimations only, and assume optimum manufacturing and application conditions. Performance may vary for indi-
vidual units, within the specified maximum and minimum limits.
[3]
V
ERR
= [(V
REF
/ 3) – V
SENSE
] / (V
REF
/ 3).
DC Control Logic
PHASE
ENABLE
1
1
1
1
0
1
0
1
X
0
1
0
0
0
MODE
1
0
1
0
1
0
0
OUTA
H
H
L
L
L
L
H
OUTB
L
L
H
H
L
H
L
Function
Forward (slow decay SR)
Forward (fast decay SR)
Reverse (slow decay SR)
Reverse (fast decay SR)
Brake (slow decay SR)
Fast decay SR*
Fast decay SR*
* To prevent reversal of current during fast decay SR – the outputs will go to the high impedance state as the current gets near zero.
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
4