ETC 2SA-10

2SA-10
November 2004
2SA-10
Integrated 2-Axis Hall Sensor
Features
Applications
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Measures two components of a magnetic field
at the same spot.
Excellent matching of sensitivity along the two
axes.
Max. angle error from –40°C ..+125°C: < 1°
Very high sensitivity
Low quiescent current
Fabricated in standard CMOS technology
Very low hysteresis
Surface mount SOIC-8 package
2-D position sensing
Contactless potentiometer
Angular position sensor for micro motors
Miniaturized contactless encoder
Contactless rotary switch
2-D magnetic field mapping
Joystick
General Description
Sentron’s new magnetic angular sensor 2SA-10 detects the absolute angular position of a small
magnet that is positioned above the device surface. The 2SA-10 is an integrated combination of a
CMOS Hall circuit and a thin ferromagnetic disk. The CMOS circuit contains two pairs of Hall-elements
for each of the two directions parallel with the chip surface X and Y. The ferromagnetic disk amplifies
the external magnetic field and concentrates it on the Hall elements.
The 2SA-10 is ideally suited for rotary position sensing in harsh automotive and industrial
environments. It produces two linear, ratio-metric output voltages proportional to the sine and the
cosine function of the angle of the applied magnetic field parallel to the chip surface.
The circuit is fabricated using a standard CMOS process and the ferromagnetic disk is added in a
simple post-processing step. The monolithic device incorporates Hall elements, offset cancellation
circuitry, current source, chopper stabilized amplification circuitry, parameter programming capability.
By dynamic offset cancellation any offset voltage caused by temperature variations, packaging stress
or others is strongly reduced. As a result, the device has an extremely stable signal output, is immune
to mechanical stress and is virtually immune to temperature cycling.
Therefore, the circuit features a wide application range and very high accuracy.
Page 1 of 8
Sentron AG • Baarerstrasse 73 • 6300 Zug • Switzerland • Tel: +41 (41) 711 2170 • Fax: +41 (41) 711 2188
www.sentron.ch • [email protected] •
for North America: GMW Associates • Tel: +1 (650) 802-8292 • Fax: +1 (650) 802-8298 • [email protected]
2SA-10
November 2004
Package:
SOIC-8
Pin-out:
1
2
3
4
5
6
7
8
Bx
By
CO_OUT, common output
PC, programming clock1)
VDD, Supply voltage
Y_OUT, Y-channel analog output
X_OUT, X-channel analog output
PD, programming data1)
PV, programming voltage1)
GND, Supply common
Note 1: Used for factory programming
Absolute Maximum Ratings
Symbol
VSUP
T
Parameter
Supply Voltage
Ambient Temperature
Min.
Max.
0
6
-40
Unit
Remarks
V
o
+125
C
Magnetic Input Conditions
Symbol
BMAX
2)
D fc
ω
Parameter
Min.
Max.
Unit
Remarks
Max. Induction
>1000
mT
Device saturates,but is
not damaged
Diameter of magnetic
disk
0.2
mm
See Figure 5 for
location of disk
angular speed
100’000
rpm
Note 2: At center of magnetic disc
Recommended Operating Conditions
Symbol
Parameter
VSUP
Supply Voltage
4.5
IOUT
Output Current
-1
CL
Load Capacitance
B
3)
Min.
Typ.
Max.
Unit
5
5.5
V
1
mA
1000
pF
80
mT
Magnetic Field
Remarks
Note 3: At center of magnetic disc
Page 2 of 8
Sentron AG • Baarerstrasse 73 • 6300 Zug • Switzerland • Tel: +41 (41) 711 2170 • Fax: +41 (41) 711 2188
www.sentron.ch • [email protected] •
for North America: GMW Associates • Tel: +1 (650) 802-8292 • Fax: +1 (650) 802-8298 • [email protected]
2SA-10
November 2004
Electrical Characteristics
At T=-40°C to 150°C, VSUP=4.5V to 5.5V if not otherwise specified.
Symbol
Parameter
Min.
Typ.
Max.
ISUP
Supply Current
CO_OUT
Common (reference)
Output Voltage 4)
BW
Bandwidth: DC to
16
18
VSUP/2
-20mV
VSUP/2
VSUP/2
+20mV
10
15
18
Unit
Test conditions
mA
IOUT=0mA
kHz
Note 4: Ratio-metric (proportional to VSUP )
Analog Output-Characteristics 5,6)
With VSUP= 5V and in the temperature range -40oC to 150oC, if not otherwise specified.
Symbol
Parameter
Min.
Typ. Max. Unit
Test conditions
S
Magnetic Sensitivity 6)
∆S/S∆T
Magnetic Sensitivity
Temperature drift
Sx/Sy
Magnetic Sensitivity
mismatch (X-Y) 6)
∠Sx-Sy
Phase matching
Voff
Offset Voltage
∆Voff/∆T
Offset Voltage Temperature
drift
BFS 7,8)
40
50
-0.05
60
0.05
V/T
%/°C
IOUT=0mA
T=-40°C to 150°C
0
2
%
B = BL 7)
-0.3
0
0.3
°
B = BL 7)
-10
0
10
mV
B=0T 7),
IOUT=0mA
T=-20°C to 80°C
mV/°C
B=0T 7),
IOUT=0mA
-0.05
0.05
Full Scale Magnetic Field
Range
-45
45
mT
BL 7,8)
Linear Magnetic Field
Range
-40
40
mT
NL
Non Linearity
0.1
0.2
%
For B ≤ BL 7)
0.5
1
%
For B ≤ BFS 7)
∆Bnoise 7)
Input referred magnetic
noise spectrum density
(RMS)
750
nT/ Hz
BW=1Hz to 10kHz
X_OUT
max
Max. full scale output
voltage
5%
VSUP
95%
VSUP
V
|B| ≥ 50mT
Y_OUT
max
Max. full scale output
voltage
5%
VSUP
95%
VSUP
V
|B| ≥ 50mT
Hys max
Maximum Hysteresis
0.03
% BFS
|B| ≥ BMAX
Note 5: When the analog output pins X_OUT and Y_OUT are used in differential mode (i.e. Vx=X_OUT-CO_OUT)
Note 6: Ratio-metric (proportional to VSUP )
Note 7: At center of magnetic disk
Note 8: The 2SA-10 can also be ordered with Sensitivity of 25V/T for BL=60mT and BFS=80mT
Page 3 of 8
Sentron AG • Baarerstrasse 73 • 6300 Zug • Switzerland • Tel: +41 (41) 711 2170 • Fax: +41 (41) 711 2188
www.sentron.ch • [email protected] •
for North America: GMW Associates • Tel: +1 (650) 802-8292 • Fax: +1 (650) 802-8298 • [email protected]
2SA-10
November 2004
Block Diagram 2SA-10
Fig. 1
Block Diagram 2SA-10
Connection Diagram 2SA-10
For reliable operation within the specifications the sensor must be connected
as follows:
IMPORTANT
Connect Pin 6 (PD) to Pin 8 (GND)
Connect Pin 2 (PC) to Pin 3 (Vdd)
Connect Pin 7 (PV) to Pin 3 (Vdd)
Put a 100nF capacitor close to the chip between Pin 3 (Vdd) and Pin 8 (GND)
VSUP
2SA-10
1 CO_Out
GND 8
2 PC
PV 7
3 Vdd
PD 6
100nF*
4 Y_Out
GND
GND
X_Out 5
*
If the supply voltage is disturbed by EMI it can be useful to place a second capacitor (100pF,
ceramic) parallel to the 100nF capacitor.
Fig. 2
Connection diagram of 2SA-10
Page 4 of 8
Sentron AG • Baarerstrasse 73 • 6300 Zug • Switzerland • Tel: +41 (41) 711 2170 • Fax: +41 (41) 711 2188
www.sentron.ch • [email protected] •
for North America: GMW Associates • Tel: +1 (650) 802-8292 • Fax: +1 (650) 802-8298 • [email protected]
2SA-10
November 2004
Package dimensions SOIC-8
Bx, By : Magnetic sensitive directions
Bx
By
Fig. 3
Package dimensions and magnetic sensitive directions
Dimension and Pads 2SA-10 in dice form
(all dimensions in µm)
2800
PC
VDD
1900
Y_OUT
Bx
By
X_OUT
CO_OUT
By
Bx
GND
PV
PD
Fig. 4
2SA-10 dimensions of dice
Page 5 of 8
Sentron AG • Baarerstrasse 73 • 6300 Zug • Switzerland • Tel: +41 (41) 711 2170 • Fax: +41 (41) 711 2188
www.sentron.ch • [email protected] •
for North America: GMW Associates • Tel: +1 (650) 802-8292 • Fax: +1 (650) 802-8298 • [email protected]
2SA-10
November 2004
Location of Disk
`
2.0mm
2.5 mm
0.8mm
Fig. 5
2SA-10 location of disk
Page 6 of 8
Sentron AG • Baarerstrasse 73 • 6300 Zug • Switzerland • Tel: +41 (41) 711 2170 • Fax: +41 (41) 711 2188
www.sentron.ch • [email protected] •
for North America: GMW Associates • Tel: +1 (650) 802-8292 • Fax: +1 (650) 802-8298 • [email protected]
2SA-10
November 2004
Applications
The unique integrated two-axis Hall-sensor offers a rugged, low cost solution for any rotational
reference detection. Application examples are found in contactless angular sensors and encoders, in
rotational switches, in brushless dc motors and in joysticks
The 2SA-10 is applied in a way very similar to magnetoresistive GMR and AMR angular sensors by
sensing the rotation of a magnetic field component parallel with the chip. However, the full integration
of magnetic field sensor and programmable signal conditioning circuit of the 2SA-10 offers an
exceptional cost effectiveness.
Sentron’s 2SA-10 combines the advantage of a miniaturized angular sensor solution and
simultaneously higher product performance and reliability. The features of high sensitivity, low offset
and low temperature drift meets even the most demanding requirements across many industries.
Absolute Angle Sensor
The 2SA-10 is positioned under a rotating magnet mounted at the shaft end of a
rotating axis. The magnet is magnetized diametrically, so that by rotating the shaft
the field through the sensor also rotates. The generated voltages Vx and Vy of the
2SA-10 represent the sine and cosine of the magnetic field direction. Even though
the signal amplitudes depend upon the vertical distance between sensor and
magnet, the angle information, which is calculated by the ratio of Vx and Vy is not
depending on this value. In this manner the angle sensor is very robust towards
sensitivity temperature drift, magnet temperature drift and ageing effects as well as
assembly tolerances.
Angular Position Sensor
5
Sensor Output Voltages [V]
4
3
Vx(t) = V0 * sin(w *t)
Vy(t) = V0 * cos(w *t)
2
1
0
0
60
120
180
240
300
360
Angle [°]
Page 7 of 8
Sentron AG • Baarerstrasse 73 • 6300 Zug • Switzerland • Tel: +41 (41) 711 2170 • Fax: +41 (41) 711 2188
www.sentron.ch • [email protected] •
for North America: GMW Associates • Tel: +1 (650) 802-8292 • Fax: +1 (650) 802-8298 • [email protected]
2SA-10
November 2004
Linear Position Sensor
The 2SA-10 is positioned in the vicinity underneath a small permanent magnet with round
shape. The magnetization axis of the magnet is perpendicular to the sensor plane. When the
magnet moves parallel to the plane, the magnetic field at the sensor rotates. The output
signal Vx of the 2SA-10 behaves like X*B/r^2 and the output signal Vy like Y*B/r^2 with X and
Y being the coordinates of the magnet with respect to the sensor, B being the field strength at
the sensor and r being the distance between magnet and sensor. If the magnet now moves
parallel to the x-axis, the coordinate Y is constant and the ratio Vx/Vy = X/const. is a very
linear measure of the position of the magnet. Using a second 2SA-10 sensor the principle can
be extended to very linear two-dimensional position sensing.
1.50
0.15
1.00
0.10
0.50
0.05
0.00
0.00
-0.50
-0.05
-0.10
-3.00
-2.00
-1.00
0.00
Vx
Vy
X/Y
Linear (X/Y)
1.00
2.00
ratio Vx/Vy
Output voltage [mV]
Output Signals X- and Y-Axis
0.20
-1.00
-1.50
3.00
displacement X [mm]
Position Sensor / Joystick
The 2SA-10 is positioned in the
rotation center of a joystick
control handle, which holds a
permanent magnet at its lower
end. In centered position the field
emanating from the magnet is
exactly perpendicular to the chip
surface and the sensor output is
zero for X and Y. As soon as the
stick is inclined, the sensor output
becomes positive or negative on
X and Y. The output signal is
linear with the inclination angle
for a range of about ± 30° of
inclination
Please contact us for documentation such as application notes, technical papers and others.
Page 8 of 8
Sentron AG • Baarerstrasse 73 • 6300 Zug • Switzerland • Tel: +41 (41) 711 2170 • Fax: +41 (41) 711 2188
www.sentron.ch • [email protected] •
for North America: GMW Associates • Tel: +1 (650) 802-8292 • Fax: +1 (650) 802-8298 • [email protected]