HAL 710/730

May/2007

PRODUCT INFORMATION

HAL

710/730

Hall-Effect Sensors with Direction Detection

PRODUCT INFORMATION

The HAL 710/730 Hall switch family is pro-

duced in CMOS technology. The sensors

include two independent temperature-com-

pensated Hall plates each equipped with

active offset compensation and a compara-

tor. The sensors provide two open-drain

outputs – one for “count” and one for “direc-

tion” detection.

The comparator compares the actual mag-

netic flux through the Hall plates (Hall volt-

age) with the fixed reference values (switch-

ing points). The first comparator directly

switches the count output. The phase shift

between both comparators determine the

state of the direction output.

The active offset compensation leads to

magnetic parameters which are robust

against mechanical stress effects. In addi-

tion, the magnetic characteristics are con-

stant over the full supply voltage and tem-

perature range.

The sensors are designed for industrial and

automotive applications and operate with

supply voltages from 3.8 V to 24 V in the

ambient temperature range from −40 °C up

to 125 °C.

The HAL 710/730 family is available in the

SMD package SOT-89B-3.

Features

◆ Operates from 3.8 V to 24 V supply volt-

age

◆ Generation of a direction signal

◆ Operates with static magnetic fields and

dynamic magnetic fields up to 10 kHz

◆ Overvoltage protection at all pins

◆ Reverse-voltage protection at V

◆ Magnetic characteristics are robust

against mechanical stress effects

◆ Short-circuit protected open-drain out-

puts by thermal shut down

◆ Constant switching points over a wide

supply voltage and temperature range

◆ The decrease of magnetic flux density

caused by rising temperature in the sen-

sor system is compensated by a built-in

negative temperature coefficient of the

magnetic characteristics

◆ High temperature stability for automo-

tive or industrial applications

◆ High ESD rating

Major Applications

The HAL 710/730 is the optimal system

solution for applications, such as:

◆ Endposition detection

◆ RPM measurement of motors in various

applications, such as power window

◆ RPM measurements in flow meters

◆ Replacement of micro switches

PRODUCT INFORMATION

HAL 710/730

May/2007

All information and data contained in this product information are without any commitment, are not to be consid-

ered as an offer for conclusion of a contract, nor shall they be construed as to create any liability. Product or

development sample availability and delivery are exclusively subject to our respective order confirmation form. By

this publication, Micronas GmbH does not assume responsibility for patent infringements or other rights of third

parties which may result from its use.

Micronas GmbH ⋅ Hans-Bunte-Strasse 19 ⋅ D-79108 Freiburg (Germany) ⋅ P.O. Box 840 ⋅ D-79008 Freiburg (Germany)

Tel. +49-761-517-0 ⋅ Fax +49-761-517-2174 ⋅ E-mail: docservice@micronas.com

⋅ www.micronas.com

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copied, stored on a retrieval system, or transmitted

without the express written consent of Micronas GmbH.

Edition May 7, 2007; Order No. PI000115-001EN

Available Types and Switching Behavior

Type Direction Output: Definition of Output State

HAL 710 Output high, when edge of comparator 1 precedes

edge of comparator 2

HAL 730 Output high, when edge of comparator 2 precedes

edge of comparator 1

System Architecture

The Hall-effect sensor is a monolithic inte-

grated circuit that switches in response to

magnetic fields. If a magnetic field with flux

lines perpendicular to the sensitive area is

applied to the sensor, the biased Hall plate

forces a Hall voltage proportional to this

field. The Hall voltage is compared with the

actual threshold level in the comparator.

The temperature-dependent bias increases

the supply voltage of the Hall plates and

adjusts the switching points to the decreas-

ing induction of magnets at higher tempera-

tures. If the magnetic field exceeds the

threshold levels, the open-drain output

switches to the appropriate state. The built-

in hysteresis eliminates oscillation and pro-

vides switching behavior of output without

bouncing.

Magnetic offset caused by mechanical

stress is compensated for by using the

“switching offset compensation technique”.

Therefore, an internal oscillator provides a

two phase clock. The Hall voltage is sam-

pled at the end of the first phase. At the end

of the second phase, both sampled and

actual Hall voltages are averaged and com-

pared with the actual switching point.

Reverse

Voltage and

Overvoltage

Protection

Temperature

Dependent

Bias

Hysteresis

Control

Hall Plate 1

Switch

Comparator

Hall Plate 2

Switch

Comparator

Clock

Output

Count Output

Direction

Output

Direction Output

Short Circuit

and

Overvoltage

Protection

Test-Mode

Control

Detection

GND

Fig. 1: Block diagram of the HAL 710/730