3958_02 Datasheet, PDF (1/12 Pages) Allegro MicroSystems – DMOS FULL-BRIDGE PWM MOTOR DRIVER

3958
DMOS FULL-BRIDGE PWM MOTOR DRIVER
A3958SLB
CP 1
CP2 2
CP1 ₃
PHASE
θ
4
OSC 5
GROUND 6
24 VREG
23 RANGE
NC
22
NO
CONNECTION
21 OUTB
V_BB 20 LOAD SUPPLY
19 GROUND
Designed for pulse-width modulated (PWM) current control of dc
motors, the A3958SB and A3958SLB are capable of continuous output
currents to ±2 A and operating voltages to 50 V. Internal fixed off-
time PWM current-control timing circuitry can be programmed via a
serial interface to operate in slow, fast, and mixed current-decay
modes.
PHASE and ENABLE input terminals are provided for use in
controlling the speed and direction of a dc motor with externally
applied PWM-control signals. The ENABLE input can be
programmed via the serial port to PWM the bridge in fast or slow
current decay. Internal synchronous rectification control circuitry is
provided to reduce power dissipation during PWM operation.
GROUND 7
LOGIC SUPPLY 8 V_DD
ENABLE 99
DATA 10
CLOCK 11
STROBE 12
18 GROUND
17 SENSE
16 OUTA
NC
15
NO
CONNECTION
14 MODE
÷
13 REF
Dwg. PP-069A
Note that the A3958SLB(SOIC) and A3958SB
(DIP) do not share a common terminal
assignment.
ABSOLUTE MAXIMUM RATINGS
Load Supply Voltage, V_BB ...................... 50 V
Output Current, I_OUT ............................. ±2.0 A
Logic Supply Voltage, V_DD .................... 7.0 V
Input Voltage, V_IN ....... -0.3 V to V_DD + 0.3 V
Sense Voltage, V_S ................................... 0.5 V
Reference Voltage, V_REF ........................ 2.7 V
Package Power Dissipation (T_A = 25°C), P_D
A3958SB ...................................... 3.1 W*
A3958SLB .................................... 1.6 W*
Operating Temperature Range,
T_A .................................... -20°C to +85°C
Junction Temperature,
T_J .................................................. +150°C
Storage Temperature Range,
T_S .................................. -55°C to +150°C
Output current rating 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.
* Per SEMI G42-88 Specification.
Internal circuit protection includes thermal shutdown with
hysteresis, and crossover-current protection. Special power-up
sequencing is not required.
The A3958SB/SLB is supplied in a choice of two power
packages, a 24-pin plastic DIP with a copper batwing tab (package
suffix ‘B’), and a 24-pin plastic SOIC with a copper batwing tab
(package suffix ‘LB’). In both cases, the power tab is at ground
potential and needs no electrical isolation. Each package type is
available in a lead-free version (100% matte tin leadframe).
FEATURES
„ ±2 A, 50 V Continuous Output Rating
„ Low r_DS(on) Outputs (270 mΩ, Typical)
„ Programmable Mixed, Fast, and Slow Current-Decay Modes
„ Serial Interface Controls Chip Functions
„ Synchronous Rectification for Low Power Dissipation
„ Internal UVLO and Thermal-Shutdown Circuitry
„ Crossover-Current Protection
Part Number
A3958SB-T
A3958SLB-T
A3958SLBTR-T
Pb-free*
Yes
Yes
Yes
R_θJA
(°C/W)
40
40
77
R_θJT
(°C/W)
6
6
6
Package
16-Pin DIP
16-Lead SOIC
16-Lead SOIC
Packing
25 per Tube
47 per Tube
1000 per reel
*_{Pb-based variants are being phased out of the product line. The variants cited in this}
footnote are in production but have been determined to be LAST TIME BUY. This
classification indicates that sale of this device is currently restricted to existing
customer applications. The variants should not be purchased for new design
applications because obsolescence in the near future is probable. Samples are no
longer available. Status change: October 31, 2006. Deadline for receipt of LAST
TIME BUY orders: April 27, 2007. These variants include: A3958SB, A3958SLB and
A3958SLBTR.