DATA SHEET HAL 805
Micronas June 24, 2004; 6251-513-2DS 3
Programmable Linear Hall Effect Sensor
Release Note: Revision bars indicate significant
changes to the previous edition.
1. Introduction
The HAL805 is a recent member of the Micronas fam-
ily of programmable linear Hall sensors. It offers open-
circuit detection and individual programming of differ-
ent sensors which are in parallel to the same supply
voltage.
The HAL805 is an universal magnetic field sensor with
a linear output based on the Hall effect. The IC is
designed and produced in sub-micron CMOS technol-
ogy and can be used for angle or distance measure-
ments if combined with a rotating or moving magnet.
The major characteristics like magnetic field range,
sensitivity, output quiescent voltage (output voltage at
B = 0 mT), and output voltage range are programma-
ble in a non-volatile memory. The sensor has a ratio-
metric output characteristic, which means that the out-
put voltage is proportional to the magnetic flux and the
supply voltage.
The HAL805 features a temperature-compensated
Hall plate with choppered offset compensation, an A/D
converter, digital signal processing, a D/A converter
with output driver, an EEPROM memory with redun-
dancy and lock function for the calibration data, a serial
interface for programming the EEPROM, and protec-
tion devices at all pins. The internal digital signal pro-
cessing is of great benefit because analog offsets,
temperature shifts, and mechanical stress do not
degrade the sensor accuracy.
The HAL805 is programmable by modulating the sup-
ply voltage. No additional programming pin is needed.
The easy programmability allows a 2-point calibration
by adjusting the output voltage directly to the input sig-
nal (like mechanical angle, distance, or current). Indi-
vidual adjustment of each sensor during the cus-
tomer’s manufacturing process is possible. With this
calibration procedure, the tolerances of the sensor, the
magnet, and the mechanical positioning can be com-
pensated 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 fit to all common magnetic materials by pro-
gramming first and second order temperature coeffi-
cients of the Hall sensor sensitivity. This enables oper-
ation 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 sensor is designed for hostile industrial and auto-
motive applications and operates with typically 5 V
supply voltage in the ambient temperature range from
−40 °C up to 150 °C. The HAL805 is available in the
very small leaded packages TO92UT-1 and TO92UT-2.
1.1. Major Applications
Due to the sensor’s versatile programming characteris-
tics, the HAL805 is the optimal system solution for
applications such as:
– contactless potentiometers,
– angle sensors,
– distance measurements,
– magnetic field and current measurement.
WARNING:
DO NOT USE THESE SENSORS IN LIFE-
SUPPORTING SYSTEMS, AVIATION, AND
AEROSPACE APPLICATIONS.
1.2. Features
– high-precision linear Hall effect sensor with
ratiometric output and digital signal processing
– multiple programmable magnetic characteristics in a
non-volatile memory (EEPROM) with redundancy
and lock function
– open-circuit detection (ground and supply line break
detection)
– for programming an individual sensor within several
sensors in parallel to the same supply voltage, a
selection can be done via the output pin
– temperature characteristics are programmable for
matching all common magnetic materials
– programmable clamping function
– programming through a modulation of the supply
voltage
– operates from −40 °C up to 150 °C
ambient temperature
– operates from 4.5 V up to 5.5 V supply voltage in
specification and functions up to 8.5 V
– operates with static magnetic fields and dynamic
magnetic fields up to 2 kHz