
Micropower Vertical and Planar
Hall-Effect Switches
APS11700
and APS11760
16
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Functional Safety
The APS11700 and APS11760 were designed in
accordance with the international standard for
automotive functional safety, ISO 26262:2011.
These products achieve an ASIL (Automotive Safety Integrity
Level) rating of ASIL A according to the standard. The APS11700
and APS11760 are both classified as a SEooC (Safety Element
out of Context) and can be easily integrated into safety-critical
systems requiring higher ASIL ratings that incorporate external
diagnostics or use measures such as redundancy. Safety docu-
mentation will be provided to support and guide the integration
process. For further information, contact your local FAE for
A2-SIL™ documentation: www.allegromicro.com/ASIL.
Undervoltage Lockout Operation
The APS11700 and APS11760 have an internal diagnostic to
check the voltage supply (an undervoltage lockout regulator).
When the supply voltage falls below the undervoltage lockout
voltage, VCC(UV)EN, the device will enter reset, where the output
state returns to the High state (the Power-On State) until VCC is
increased to VCC(UV)DIS. The supply voltage monitor employed
by the undervoltage lockout circuit is only active during the
awake time. Therefore, undervoltage lockout can be enabled and
disabled only when the device is in the awake state. See Figure 5
for an example. When enabled, the supply current will be ICC(EN).
UVLO
Enabled
t
V
t
POR
Output State,
“L” Polarity
Supply
Voltage
Output State,
“H” Polarity
I
Supply
Current*
V
CC
(min)
V
CC(UV )DIS
V
CC(UV)EN
Power-Off
V
t
t
I
CC(DIS )
I
CC(EN)
Low
High
Key
POS
B > B
OP,
B
RP
< B < B
OP
B < B
RP
Key
POS
B > B
OP
B < B
OP
V
t
Low
High
*Micropower Duty Cycle and Period Not to Scale
POS
POS
Figure 5: Undervoltage Lockout Behavior
Once VCC is restored to above VCC(UV)DIS, the power-on
sequence begins and the output will correspond with the applied
magnetic field for B > BOP and B < BRP after tPOR has elapsed.
In the case the supply voltage does not return to these operational
levels, or if the applied magnetic field is within the hysteresis
range, the output will remain in the power-on state.
Operation
The APS11700 and APS11760 are integrated Hall-effect sensor
ICs with an open-drain output. Table 1 offers a guide for select-
ing the output polarity configuration, further explained in the
configuration sections below. The output is an open-drain NMOS
transistor that actuates in response to a magnetic field. The direc-
tion of the applied magnetic field is perpendicular to the branded
face for the APS11700, and parallel with the branded face for
the APS11760; see Figure 6 for an illustration. The devices are
offered in two packages: the UA package, a 3-pin through-hole
mounting configuration, or in the LH package, a 3-pin surface-
mount configuration. See the Selection Guide for a complete list
of available options.
Configurations xSLx and xSHx. The unipolar output of these
devices is actuated when a south-polarity magnetic field perpen-
dicular to the Hall element exceeds the operate point threshold,
BOPS. When BOPS is exceeded, the xSLx output turns on (goes
Figure 6: Magnetic Sensing Orientations
APS11700 LH (Panel A), APS11700 UA (Panel B),
APS11760 LH (Panel C) and APS11760 UA (Panel D)
2
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