DATA SHEET
HAL856
peratures from
−40
°C up to 150 °C. The HAL856 is
available in the very small leaded packages TO92UT-1
and TO92UT-2.
Programmable Linear Hall-Effect Sensor with Arbi-
trary Output Characteristic (2-Wire)
Release Note: Revision bars indicate significant
changes to the previous edition.
1.1. Major Applications
1. Introduction
The HAL856 is a member of the Micronas family of
programmable linear Hall sensors. The HAL856 offers
an arbitrary output characteristic and a 2-wire output
interface.
The HAL856 is an universal magnetic field sensor
based on the Hall effect. The IC is designed and pro-
duced in sub-micron CMOS technology and can be
used for angle or distance measurements if combined
with a rotating or moving magnet. The major charac-
teristics like magnetic field range, output characteristic,
output format, sensitivity, shift (offset), PWM period,
low and high output current, and the temperature coef-
ficients are programmable in a non-volatile memory.
The output characteristic can be set with 32 setpoints.
The HAL856 features a temperature-compensated
Hall plate with choppered offset compensation, an
A/D-converter, digital signal processing, an EEPROM
memory with redundancy and lock function for the cali-
bration data, a serial interface for programming the
EEPROM, and protection devices at all pins. The inter-
nal digital signal processing is of great benefit because
analog offsets, temperature shifts, and mechanical
stress do not degrade the sensor accuracy.
The HAL856 is programmable by means of modulat-
ing the supply voltage. No additional programming pin
is needed. The easy programmability allows a 2-point
calibration by adjusting the output signal directly to the
input signal (like mechanical angle, distance, or cur-
rent). Individual adjustment of each sensor during the
customer’s manufacturing process is possible. With
this calibration procedure, the tolerances of the sensor,
the magnet, and the mechanical positioning can be
compensated in the final assembly. This offers a low-
cost alternative for all applications that presently need
mechanical adjustment or laser trimming for calibrating
the system.
In addition, the temperature compensation of the Hall
IC can be fitted to all common magnetic materials, by
programming first and second order temperature coef-
ficients of the Hall sensor sensitivity. This enables
operation over the full temperature range with high
accuracy.
The calculation of the individual sensor characteristics
and the programming of the EEPROM memory can
easily be done with a PC and the application kit from
Micronas. The sensors are designed for automotive or
industrial applications. They operate with ambient tem-
Due to the sensor’s versatile programming character-
istics, the HAL856 is the optimal system solution for
applications such as:
– contactless potentiometers,
– rotary position measurement (e.g., pedal sensor),
– fluid level measurement,
– linear position detection, and
– magnetic field detection.
1.2. Features
– high-precision linear Hall effect sensors with differ-
ent output formats
– various programmable magnetic characteristics with
non-volatile memory
– programmable output characteristic
(32 setpoints with 9-bit resolution)
– programmable output formats
(PWM or serial Biphase-M)
– programmable PWM period
– programmable output current source
(low and high current)
– digital signal processing
– temperature characteristics programmable for
matching all common magnetic materials
– programming by modulation of the supply voltage
– lock function and built-in redundancy for EEPROM
memory
– operates from –40 °C up to 150 °C ambient temper-
ature
– operates from 4.5 V up to 18 V supply voltage
– operates with static magnetic fields and dynamic
magnetic fields up to 2 kHz
– choppered offset compensation
– overvoltage protection on all pins
– reverse-voltage protection on V
DD
pin
– magnetic characteristics extremely robust against
mechanical stress
– short-circuit-protected output
– EMC-optimized design
– programmable slew rate for optimized EMI behavior
– single-wire interface possible
Micronas
March 23, 2010; DSH000142_002EN
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MICRONAS [ MICRONAS ]
