A1172_13 Datasheet, PDF (1/11 Pages) Allegro MicroSystems – Micropower Ultra-Sensitive Hall-Ef fect Switch

A1172
Micropower Ultra-Sensitive Hall-Effect Switch
Features and Benefits
▪ Micropower operation
▪ Operation with either north or south pole—
no magnetic orientation required during assembly
▪ 1.65 to 3.5 V battery operation
▪ Chopper stabilization
▫ Superior temperature stability
▫ Extremely low switchpoint drift
▫ Insensitive to physical stress
▪ Solid state reliability
▪ Small size: WLCSP (≈ 1 mm × 1 mm × 0.5 mm)
▪ Complementary, push-pull outputs eliminate need for
pull-up resistor
Package: 4 pin WLCSP (suffix CG)
Description
The A1172 is an ultra-sensitive, pole-independent Hall-effect
switch with a latched digital output. It features operation at
low supply currents and voltages, making it ideal for battery-
operated electronics. The 1.65 to 3.5 V operating supply
voltage and unique clocking algorithm reduce the average
operating power requirements to less than 15 μW with a
2.75 V supply.
The A1172 has two push-pull output structures. Omnipolar
activation for the output function is available on each output
structure. As such, either a north or south pole of sufficient
strength turns the available outputs off or on. The A1172
contains two complementary outputs. Therefore, for a fixed
magnetic field, one output will be in a high voltage state and
one output will be in a low voltage state.
Improved stability is made possible through dynamic offset
cancellation using chopper stabilization, which reduces the
residual offset voltage normally caused by device overmolding,
temperature dependencies, and thermal stress. This device
Not to scale
VDD
Continued on the next page…
Engineering samples available on a limited basis. Contact your local
sales or applications support office for additional information.
Functional Block Diagram
1172-DS, Rev. 5
Clock / Logic
Amp
Low-Pass
Filter
GND
Latch
Latch
VOUTPS
VOUTPN