A3935 Allegro MicroSystems, Inc., A3935 Datasheet - Page 11

• Manufacturer Part Number: A3935
• Description: Three-Phase Power MOSFET Controller
• Manufacturer: Allegro MicroSystems, Inc.

NOTES: x = “Little x ”indicates A, B, or C phase.
www.allegromicro.com
Fault Mode
No Fault
Short-to-Battery
Short-to-Ground
Bridge (V
V
V
V
V
Thermal Shutdown'
REG
BAT
BAT
DD
"
#
$
%
&
'
Z = High-impedance state.
X = “Capital X “ indicates a “don’t care”.
Undervoltage'
Undervoltage
Overvoltage
Undervoltage'
= Depends on xLO input, xHI input, and ENABLE. See Input Logic table.
= Short-to-battery can only be detected when the corresponding GLx = 1. This fault is not detected when ENABLE = 0.
= Short-to-ground can only be detected when the corresponding GHx = 1. This fault is not detected when ENABLE = 0.
= Bridge fault appears as a short-to-ground fault on all motor phases. This fault is not detected when ENABLE = 0.
= Off, only because V
= These faults are not only reported but action is taken by the internal logic to protect the A3935 and the system.
DRAIN
ENABLE xLO
) Fault
0
1
1
1
1
ENABLE
BOOST
Input
X
0
0
1
1
1#
1$
1%
X
X
X
X
X
X
V
xHI
Functional Description (cont’d)
BAT
X
0
1
0
1
FAULT
is above the voltage threshold of the regulator’s voltage control loop.
1
0
0
0
0
0
0
0
0
GLx
0
0
0
1
0
Fault Responses
OVFLT
Input Logic
GHx
Z
Z
0
0
1
0
0
0
0
0
0
0
1
0
Mode of Operation
All gate drive outputs low
Both gate drive outputs low
High side on
Low side on
XOR circuitry prevents shoot-through
UVFLT
Z
Z
0
0
0
0
0
0
1
Boost
OFF&
Reg.
OFF
OFF
OFF
MOSFET CONTROLLER
ON
ON
ON
ON
ON
THREE-PHASE POWER
Reg.
V
OFF
OFF
OFF
ON
ON
ON
ON
ON
ON
REG
GHx
"
"
"
"
"
"
0
0
0
GLx
3935
"
"
"
"
"
"
0
0
0
11