A3938SLD Allegro Microsystems Inc, A3938SLD Datasheet - Page 7

• Manufacturer Part Number: A3938SLD
• Description: IC CTRLR MOSFET 3PH 38-TSSOP
• Manufacturer: Allegro Microsystems Inc

Specifications of A3938SLD

• Applications: DC Motor Controller, Brushless (BLDC), 3 Phase
• Number Of Outputs: 1
• Voltage - Supply: 18 V ~ 50 V
• Operating Temperature: -20°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 38-TSSOP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Current - Output: -
• Voltage - Load: -

A3938
VBB.
for power MOSFETs. It is good practice to connect a decou-
pling capacitor from this pin to AGND, as close to the device
pins as possible.
REF.
applied here sets the peak load current according to the fol-
lowing equation:
LCAP.
low current for DEAD pin and FAULT pin. Connection for
0.1 μF external capacitor for decoupling.
Analog input to current limit comparator. Voltage
Motor power supply connection for the A3938 and
5 V reference to power internal logic and provide
* Low-side, only, Synchronous Rectifi cation mode.
**See Commutation Truth Table for meaning of “both” and "selected."
Commutation Truth Table
Input Logic
MODE
H1
1
1
1
0
0
0
1
1
1
0
0
0
0*
0*
X
1
1
H2
0
0
1
1
1
0
0
0
1
1
1
0
I
PWM
TRIP
X
0
1
0
1
H3
= V
1
0
0
0
1
1
1
0
0
0
1
1
REF
RESET
DIR
/ R
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
1
SENSE
GLA
0
0
1
1
0
0
1
0
0
0
0
1
Slow Decay
Slow decay
Fast Decay
Fast decay
Quadrant
Three-Phase Power MOSFET Controller
X
GLB
0
0
0
0
1
1
0
1
1
0
0
0
PWM chop – current decay with opposite of selected low-
side drivers ON.
Selected drivers ON. If current limiting, opposite of selected
low-side drivers ON.
PWM chop – current decay with both low-side drivers ON.
Selected drivers ON. If current limiting, both low-side drivers ON.
All high-side drivers OFF, low-sides see BRKSEL stored.
Clears storable faults.
GLC
1
1
0
0
0
0
0
0
0
1
1
0
DEAD.
is selected to adjust turn-off time to turn-on time. This
delay is needed to prevent cross-conduction in the external
power MOSFETs. See the section Application Information
for details on setting dead time.
SENSE.
Voltage representing load current appears on this pin. Voltage
transients that are seen at this pin when the drivers turn on
are ignored for period of time, t
AGND.
PGND.
connected to the PCB power ground.
GHA
1
0
0
0
0
1
0
0
1
1
0
0
Analog input. A resistor between DEAD and LCAP
Analog reference ground.
Return for low-side gate drivers. This should be
GHB
Mode of Operation**
Analog input to the current limit comparator.
0
1
1
0
0
0
0
0
0
0
1
1
GHC
0
0
0
1
1
0
1
1
0
0
0
0
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
SA
LO
LO
LO
LO
HI
HI
HI
HI
Z
Z
Z
Z
BLANK
.
SB
LO
LO
LO
LO
HI
HI
HI
HI
Z
Z
Z
Z
SC
LO
LO
LO
LO
HI
HI
HI
HI
Z
Z
Z
Z
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