8906 Datasheet, PDF (1/12 Pages) Allegro MicroSystems – BIDIRECTIONAL 3-PHASE BRUSHLESS DC MOTOR CONTROLLER/DRIVER WITH BACK-EMF SENSING

8906
BIDIRECTIONAL 3-PHASE BRUSHLESS DC MOTOR
CONTROLLER/DRIVER WITH BACK-EMF SENSING
LOAD
SUPPLY
1
V _BB
COMMUTATION
DELAY
C _D2 2
C _WD 3
CST ₄
24 C _D1
23 DATA IN
22 CLOCK
21 _{CHIP SELECT}
OUTA 5
GROUND 6
20 RESET
19 GROUND
GROUND ₇
18 _GROUND
OUTB 8
MUX
17 DATA OUT
OUTC 99
CENTERTAP 10
BRAKE 11
C _RES 12
BOOST
CHARGE
PUMP
FLL
16 OSCILLATOR
VDD ₁₅
LOGIC
SUPPLY
14 ^SECTOR
DATA
13 FILTER
Dwg. PP-040B
ABSOLUTE MAXIMUM RATINGS
at T_A = +25°C
Load Supply Voltage, V_BB . . . . . . . . . . 14 V
Output Current, I_OUT . . . . . . . . . . . . ±1.25 A
Logic Supply Voltage, V_DD . . . . . . . . . 6.0 V
Logic Input Voltage Range,
V_IN . . . . . . . . . . . -0.3 V to V_DD + 0.3 V
Package Power Dissipation, P_D See Graph
Operating Temperature Range,
T_A . . . . . . . . . . . . . . . . . . 0°C to +70°C
Junction Temperature, T_J . . . . . . . +150°C†
Storage Temperature Range,
T_S . . . . . . . . . . . . . . . -55°C to +150°C
† Fault conditions that produce excessive junction
temperature will activate device thermal shutdown
circuitry. These conditions can be tolerated, but
should be avoided.
Output current rating may be restricted to a value
determined by system concerns and factors.
These include: system duty cycle and timing,
ambient temperature, and use of any heatsinking
and/or forced cooling. For reliable operation, the
specified maximum junction temperature should
not be exceeded.
The A8906CLB is a bidirectional three-phase brushless dc motor
controller/driver. The three half-bridge outputs are low on-resistance n-
channel DMOS devices capable of driving up to 1 A. The A8906CLB
provides complete, reliable, self-contained back-EMF sensing motor
startup and running algorithms. A programmable digital frequency-
locked loop speed control circuit together with the linear current control
circuitry provides precise motor speed regulation.
A serial port allows the user to program various features and
modes of operation, such as the speed control parameters, rotational
direction, startup current limit, sleep mode, diagnostic modes, and
others.
The A8906CLB is fabricated in Allegro’s BCD (Bipolar CMOS
DMOS) process, an advanced mixed-signal technology that combines
bipolar, analog and digital CMOS, and DMOS power devices. The
A8906CLB is provided in a 24-lead wide-body SOIC batwing package.
It provides for the smallest possible construction in surface-mount
applications.
PRELIMINARY INFORMATION
FEATURES
(Subject to change without notice)
s DMOS Outputs
March 1, 1999
s Low r_DS(on)
s Startup Commutation Circuitry
s Back-EMF Commutation Circuitry
s Direction Control
s Serial Port Interface
s Frequency-Locked Loop Speed Control
s Sector Data Tachometer Signal Input
s Programmable Start-Up Current
s Diagnostics Mode
s Sleep Mode
s Linear Current Control
s Internal Current Sensing
s Dynamic Braking Through Serial Port
s Power-Down Dynamic Braking
s System Diagnostics Data Out
s Data Out Ported in Real Time
s Internal Thermal Shutdown Circuitry
Always order by complete part number, e.g., A8906CLB .