Automotive 3-Phase BLDC Controller and MOSFET Driver
Features and Benefits
High current 3-phase gate drive for N-channel MOSFETs
Synchronous rectification
Cross-conduction protection
Charge pump and top-off charge pump for 100% PWM
Integrated commutation decoder logic
Operation over 5.5 to 50 V supply voltage range
Extensive diagnostics output
Provides +5 V Hall sensor power
Low-current sleep mode
Package: 48 Lead LQFP with exposed
thermal pad (suffix JP)
Description
The A3930 and A3931 are 3-phase brushless DC (BLDC) motor
controllers for use with N-channel external power MOSFETs.
They incorporate much of the circuitry required to design a
cost effective three-phase motor drive system, and have been
specifically designed for automotive applications.
A key automotive requirement is functionality over a wide
input supply range. A unique charge pump regulator provides
adequate (>10 V) gate drive for battery voltages down to 7 V,
and allows the device to operate with a reduced gate drive at
battery voltages down to 5.5 V. Power dissipation in the charge
pump is minimized by switching from a voltage doubling mode
at low supply voltage to a dropout mode at the nominal running
voltage of 14 V.
A bootstrap capacitor is used to provide the above-battery
supply voltage required for N-channel MOSFETs. An internal
charge pump for the high-side drive allows for DC (100% duty
cycle) operation.
Internal fixed-frequency PWM current control circuitry can
be used to regulate the maximum load current. The peak
load current limit is set by the selection of an input reference
voltage and external sensing resistor. The PWM frequency is
set by a user-selected external RC timing network. For added
flexibility, the PWM input can be used to provide speed and
Approximate Scale 1:1
Continued on the next page…
T ypical Application
3930-DS Rev. 2
A3930 and
Automotive 3-Phase BLDC Controller
A3931
Description (continued)
torque control, allowing the internal current control circuit to set
the maximum current limit.
Efficiency is enhanced by using synchronous rectification. The
power FETs are protected from shoot-through by integrated
crossover control with dead time. The dead time can be set by a
single external resistor.
The A3930 and A3931 only differ in their response to the all-zero
Selection Guide
Part NumberOptionPackingTerminalsPackage
A3930KJP-THall short detection250 pieces/tray
A3930KJPTR-THall short detection1500 pieces/reel
A3931KJP-TPre-positioning250 pieces/tray
A3931KJPTR-TPre-positioning1500 pieces/reel
combination on the Hall inputs. In this state, the A3930 indicates
a logic fault, but the A3931 pre-positions the motor in an unstable
starting position suitable for start-up algorithms in microprocessordriven “sensor-less” control systems.
Both devices are supplied in a 48-pin LQFP with exposed thermal
pad. This is a small footprint (81 mm2) power package, that is lead
(Pb) free, with 100% matte tin leadframe plating.
48LQFP surface mount
and MOSFET Driver
Absolute Maximum Ratings
ParameterSymbolConditionsRatingUnits
Load Supply VoltageV
V
Logic Input/Output Voltage
Output Voltage Range
Operating Temperature Range (K)T
Junction TemperatureT
Transient Junction TemperatureT
Storage Temperature RangeT
ESD Rating, Human Body Model
ESD Rating, Charged Device ModelAEC-Q100-011, all pins1050V
RESET
V
V
V
V
VBB pin–0.3 to 50V
BB
RESET pin input–0.3 to 6V
Remaining logic pins–0.3 to 7V
GHA, GHB, and GHC pinsVSx to VSx+ 15V
GHx
GLA, GLB, and GLC pins–5 to 16V
GLx
CA, CB, and CC pinsVSx+ 15V
Cx
SA, SB, and SC pins–5 to 55V
Sx
CSP, CSN, and LSS pins–4 to 6.5V
CSO, VDSTH pins–0.3 to 6.5V
VDRAIN pin–0.3 to 55V
A
J
Overtemperature event not exceeding 1 s, lifetime duration not exceed-
tJ
ing 10 hr; guaranteed by design
characterization
S
AEC-Q100-002, all pins except CP12000V
AEC-Q100-002, pin CP11000V
–40 to 150°C
–55 to 150°C
150°C
175°C
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
2
A3930 and
Automotive 3-Phase BLDC Controller
A3931
QV5
VBAT+
V5BD
CV5
MODE
COAST
BRAKE
RESET
DIR
and MOSFET Driver
Functional Block Diagram
CP
VBB
V5
H1
+5V Ref
Control
Logic
Phase A of three phases
CP1CP2
Charge
Pump
Regulator
Charge
Pump
Boostrap
Monitor
High-Side
Drive
VREG
VDRAIN
CA
GHA
SA
CREG
CBOOTA
RGHA
P
V5
H1
H2
H3
&C
&B
H2
H3
RDEAD
PWM
TACHO
DIRO
ESF
FF1
FF2
Pad
Diagnostics and
Protection
–UVLO
–TSD
–Short to Supply
–Short to Ground
–Shorted Winding
–Low Load
VDSTH
RC
Q
OSC
VREG
Low-Side
Drive
R
Blanking
S
REF
CSOUT
CTRT
AGND
GLA
RGLA
LSS
TEST
CSP
CSN
P
&A
RSENSE
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
FFx Fault Output (Open Drain)V
FFx Fault Output Leakage Current
2
TACHO and DIRO Output High VoltageV
TACHO and DIRO Output Low VoltageV
Input Low VoltageV
Input High Voltage (Except RESET)V
RESET Input High VoltageV
Input HysteresisV
Input Current (Except H1, H2, H3, and
RESET)
2
RESET Input Pull-Down ResistorR
Hx Input Pull-Up ResistorR
Current Sense Differential Amplifier
Input Bias Current
Input Offset Current
2
2
CSP Input ResistanceR
CSN Input ResistanceR
Differential Input VoltageV
Output Offset VoltageV
Output Offset Voltage DriftV
Input Common Mode RangeV
Differential Input Voltage GainA
Low Output Voltage ErrorV
DC Common Mode GainA
Source Resistancer
Output Dynamic RangeV
Output Current – SinkI
Output Current – Source
2
p(off)
DEAD
OL
I
OH
OH
OL
IL
IH
IHR
IHys
I
IN
PD
PU
I
IBS
I
IOS
CSP
CSN
ID
OOS
OOS(t)
CM
V
err
CMdc
CSOUT
CSOUT
CSOUT(sink)VCSOUT
I
CSOUT(source)VCSOUT
and MOSFET Driver
= –40°C to 150°C, V
J
From Hall input change to unloaded
gate output change
From other control input change to
unloaded gate output change
R
= 5 k –180–ns
DEAD
R
= 50 k8359601090ns
DEAD
R
= 400 k–3.3–s
DEAD
= 7 to 45 V, unless otherwise noted
BB
300500700ns
–150200ns
RDEAD = tied to V5–6–s
I
= 1 mA, fault asserted––0.4V
OL
VO = 5 V, fault not asserted–1–1A
I
= –1 mAV5 – 1 V––V
OH
I
= 1 mA––0.4V
OL
––0.8V
2––V
2.2––V
300500–mV
–1–1A
V
= 5 V–50–k
IN
V
= 0 V–100–k
IN
CSP = CSN = 0 V–250–200–150A
CSP = CSN = 0 V–10–10A
Measured with respect to AGND–80–k
Measured with respect to AGND–4–k
V