Description
The Allegro
®
A1101-A1104 and A1106 Hall-effect switches
are next generation replacements for the popular Allegro
312x and 314x lines of unipolar switches. The A110x family,
produced with BiCMOS technology, consists of devices that
feature fast power-on time and low-noise operation. Device
programming is performed after packaging, to ensure increased
switchpoint accuracy by eliminating offsets that can be induced
by package stress. Unique Hall element geometries and low-
offset amplifiers help to minimize noise and to reduce the
residual offset voltage normally caused by device overmolding,
temperature excursions, and thermal stress.
The A1101-A1104 and A1106 Hall-effect switches include
the following on a single silicon chip: voltage regulator,
Hall-voltage generator, small-signal amplifier, Schmitt
trigger, and NMOS output transistor. The integrated voltage
regulator permits operation from 3.8 to 24 V. The extensive
on-board protection circuitry makes possible a ±30 V absolute
maximum voltage rating for superior protection in automotive
and industrial motor commutation applications, without adding
A1101-DS, Rev. 3
Features and Benefits
▪ Continuous-time operation
▫ Fast power-on time
▫ Low noise
▪ Stable operation over full operating temperature range
▪ Reverse battery protection
▪ Solid-state reliability
▪ Factory-programmed at end-of-line for optimum
performance
▪ Robust EMC performance
▪ High ESD rating
▪ Regulator stability without a bypass capacitor
Continuous-Time Switch Family
Continued on the next page…
Packages: 3 pin SOT23W (suffix LH), and
3 pin SIP (suffix UA)
Functional Block Diagram
Not to scale
A1 101, A1102, A1 103, A1104, and A1 106
Amp
Regulator
GND
VCC
VOUT
OffsetGain
Trim
Control
To all subcircuits
