Philips kmi15 DATASHEETS

DISCRETE SEMICONDUCTORS

DATA SH EET

ook, halfpage

M3D281

KMI15/2

Integrated rotational speed sensor

Product specification
Supersedes data of 2000 Jun 26

2000 Sep 05

Philips Semiconductors Product specification

Integrated rotational speed sensor KMI15/2

FEATURES

• Digital current output signal

• Zero speed capability

• Wide air gap

• Wide temperature range

• Insensitive to vibration

• EMC resistant.

DESCRIPTION

The KMI15/2 sensor detects (rotational) speed and
reference mark detection of magnetized targets

(1)

.
The sensor consists of a magnetoresistive sensor
element, a signal conditioning integrated circuit in bipolar
technology and a magnetized ferrite magnet.
The frequency of the digital current output signal is
proportional to the rotational speed of a gear wheel.

CAUTION

Donotpresstwoormoreproductstogetheragainsttheir
magnetic forces.

PINNING

PIN DESCRIPTION

1V

CC

2V−

handbook, halfpage

12

MBH780

(1) The sensor contains a customized integratedcircuit.Usagein

hydraulic brake systems and in systems with active brake
control is forbidden. For all other applications, higher
temperature versions of up to 150
request.

°C are available on

Fig.1 Simplified outline; (SOT453A).

QUICK REFERENCE DATA

SYMBOL PARAMETER MIN. TYP. MAX. UNIT

V

CC

I

CC (low)

I

CC (high)

f

t

T

amb

DC supply voltage 0.5 12 16 V
current output signal low − 7 − mA
current output signal high − 14 − mA
operating frequency 0 − 25000 Hz
ambient operating temperature −40 − +85 °C

2000 Sep 05 2

Philips Semiconductors Product specification

Integrated rotational speed sensor KMI15/2

LIMITING VALUES

In accordance with Absolute Maximum Rating System (IEC 60134).

SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT

V

CC

T

stg

T

amb

T

sld

CHARACTERISTICS

T

=25°C; VCC=12V; ft= 2 kHz; test circuit: see Fig.7; RL= 115 Ω.

amb

SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT

I

CC (low)

I

CC (high)

t

r

t

f

t

d

f

t

Hs

LH

Hs

HL

Hs magnetic switching

DC supply voltage T

= −40 to +85 °C; RL= 115 Ω 0.5 16 V

amb

storage temperature −40 +150 °C
operating ambient temperature −40 +85 °C
soldering temperature t ≤ 10 s − 260 °C
output short-circuit duration to GND continuous

current output signal low see Fig.6 5.6 7.0 8.4 mA
current output signal high see Fig.6 11.2 14.0 16.8 mA
output signal rise time CL= 100 pF; 10 to 90% value − 0.5 −µs
output signal fall time CL= 100 pF; 10 to 90% value − 0.7 −µs
switching delay time between stimulation pulse (generated by

− 1 −µs

a coil) and output signal
operating frequency for both rotation directions 0 − 25000 Hz
magnetic switching field

0.05 0.3 0.8 kA/m

strength
magnetic switching field

0.05 0.3 0.8 kA/m

strength

0.15 − 1.6 kA/m

hysteresis

2000 Sep 05 3

Philips Semiconductors Product specification

Integrated rotational speed sensor KMI15/2

FUNCTIONAL DESCRIPTION

The KMI15/2 sensor is sensitive to magnetic fields.
The functional principle is shown in Fig.3. The field lines of
a magnetized target are shown in Fig.3 as a straight target
(it could also be circular e.g. for rotational speed
measurement). If a sensor KMI15/2 is moved as shown in
this field, either of the magnetic field components HsHLor
HsLHis dominant, and forces the sensor to switch to either
the high current (14 mA) or to the low current (7 mA).
Oscillation of the sensor output signal is avoided by the
implementation of a hysteresis into the signal conditioning
electronic.

The MR sensor is stabilized by a permanent magnet
applying a continuous magnetic field of ≥6 kA/m to the
sensor. If the magnetic field given by the magnetized
target errors like frequency doubling might occur.
The magnetoresistive sensor element signal is amplified,
temperature compensated and forwarded to a
Schmitt-trigger in the conditioning integrated circuit
(Figs 4 and 5). The digital output signal levels (Fig.6) are
independent of the magnetic field condition.
A (2-wire) output current enables safe transfer of the
sensor signal to the detecting circuit (Fig.7).
The integrated circuit housing is separated from the
sensor element housing to optimize the sensor behaviour
at high temperatures.

handbook, halfpage

xx

y

magnet with
direction of
magnetization

sensor

IC

MBH777

z

Fig.2 Component detail of the KMI15/2.

2000 Sep 05 4