MR Sensor
March, 2007
NEC Corporation.
NEC Yamanashi Ltd.
What is MR sensor ?
•MR sensor is magneto-resistive sensor with built-in IC in a single-chip
comprising four magneto-resistive elements and C-MOS circuit.
•It is a magnetic sensor with high sensitivity to the magnetic field and
stable sensitivity better than hall IC.
Chip Layout
Appearance
MRSS32W MRUS71D
MRSS23E
Old Chip
New Chip
MR Elements
MRUS61C
MRUS51S
IC Circuit
Chip Internal Image
MR Elements
Protection film
Silicon
Ｐage 2
© NEC Corporation 2007
IC Circuit
Application Examples
Mobile Phone
Electronic
Dictionary
Note PC
Portable Games
Digital Camera
Digital
Video Camera
Note) Purpose of these images are only to show the application example of MR sensor.
Ｐage 3
© NEC Corporation 2007
MR Sensors for Mobile Phones
MRSS23E
MRSS32W
2.9mm
MRUS51S
2.0mm
1.1mm
8.93mm3
1.45mm
2.1mm
2.8mm
1.45mm
0.8mm
0.55mm
3.36mm3
1.6V – 3.5V
1.6V – 3.5V
1.16mm3
1.6V – 3.5V
MRUS61Ｃ ~ Leadless Package
MRUS71D ~ 2 Output operation
1.5mm
1.8mm
1.0mm
1.6mm
0.37mm
0.59mm3
1.6V – 3.5V
Ｐage 4
© NEC Corporation 2007
0.8mm
2.16mm3
2.4V – 3.6V
Product Close UP 1
Ultra Thin Package - thinner than common LEDS!
NG
Cover
0.4mm（T)
0.5mm or more（T)
0.37mm（T)
MRUS61C
LED
Keypad
0.4mm（T)
Other Sensors
*Example: Layout on Keypad
Ideal for small and thin size communication equipment or AV equipment
MRUS61C
(Ta=25±3ºC unless otherwise specified)
1.0
Item
Output
Condition
Min
Typ
Max
Unit
Source Voltage
-
-
1.6
1.8
3.5
V
Supply Current
(AVG)
Vdd=1.8V
-
3
-
uA
-
-
-40
25
85
ºC
VOH
Vdd=1.8V
I out=1mA
1.6
-
-
V
VOL
Vdd=1.8V
I out=1mA
-
-
0.2
V
Output Hon
25±3 ºC
-
1.7
2.5
mT
Output Hoff
25±3 ºC
0.8
-
-
Ambient Temperature
0.02
1.6
0.35
Output Voltage
Operating
Magnetic Field
Ｐage 5
© NEC Corporation 2007
.
Product Close UP 2
TWO Output Operation - Small sensitivity distribution
(Ta=25±3ºC unless otherwise specified)
Ordinal MR sensor
MRSS23E
0
0.5
2.2
2.5
4.5mT
Output 1
OFF
ON or OFF
ON
Detect range
2 Output MR sensor
MRSS71D
1
Output 1
2
Output 2
OFF
ON or OFF
ON
Detect range
OFF
ON or OFF
ON
Detect range
High sensitivity
(Ta=25±3ºC unless otherwise specified)
MRUS71D
Item
0.30+/-0.1
Condition
Min
Typ
Max
Unit
Source Voltage
Vdd
-
2.4
2.5
3.6
V
Supply Current
(AVG)
Vdd=2.5V
-
3
-
uA
-
-
-40
25
85
ºC
VOH
Vdd=2.5V
V io=1.8V
Pull up=33kΩ
1.71
-
-
V
-
1.5
2.5
0.5
1.2
-
Ambient Temperature
3
1.50
MAX
1.95mm
1.8mm
1
Output
MAX 0.8mm
MAX 1.5mm
1.6mm
4
Low sensitivity
Output Voltage
2
Hi-level Hon 1
0.7+/-0.15
Output1
Pin # /name
1. GND
2. Vdd (Dot marking)
3. Output 2
4. Output 1
Lo-level Hoff 1
Operating
Magnetic
Field
Hi-level Hon 2
Vdd=2.5V
Ta=25±3 ºC
mT
-
3.5
4.5
2.2
2.9
-
Output2
Lo-level Hoff 2
-Micro low power (7.5μW(typ): Vdd=2.5V)
Ｐage 6
© NEC Corporation 2007
Circuit Block
Much simpler circuit block compared to Hall ICs.
>MR sensor is CMOS output, there’s no need for a resister.
Vcc
Sampling
circuit
Op-Amp
MR sensor
Latch
circuit
Out
Gnd
R1∼R4：MR El emen t s
Vcc
Switch
Hall IC (Allegro)
© NEC Corporation 2007
LATCH
SAMPLE
& HOLD
DYNAMIC
OFFSET CANCELLATION
Hall
Ｐage 7
Need a resister
TIMING
LOGIC
OUT
GND
CMOS
CMOS
output
output
Feature
Save money & time with Design flexibility and great feature of MR sensors
Excellent service and support by NEC engineers!
¾ High Sensitivity & Small sensitivity distribution
¾ Ultra small size
¾ Dual operating magnetic pole
¾ Low source supply
¾ Professional technical support
Ｐage 8
© NEC Corporation 2007
High Sensitivity & Small Sensitivity Distribution
MR
MRsensors
sensorssensitivity
sensitivitydistribution:
distribution: OFF
OFF0.5mT
0.5mT--ON
ON2.5mT
2.5mT
0.5
MRSS23E
MRSS23E
2.2
0.8
MRSS32W
MRSS32W
0.5
MRUS51S
MRUS51S
2.5
2.2
0.8
MRUS61C
MRUS61C
0.5
2.5
2.2
3212 / Allegro
MR sensor
2.5
MRUS71D
MRUS71D
EM1671 / AKE
Small
Smallsensitivity
sensitivity
distribution
distribution
1.0
4.5
4.2
1.0
0mT
MR vs Hall IC
sensitivity comparison
2mT
4mT
6mT
Small
© NEC Corporation 2007
8mT
Cost Effective
Magnet size
Ｐage 9
Hall IC
5.5
Big
sensitivity
Ultra Small Size
•Volume of MRUS61C is 0.59 mm3
•Height of MRUS61C is only 0.37 mm
Size Comparison
Length
(mm)
Area
(mm2)
Height
(mm)
Volume
(mm3)
MRUS61C
1.0
1.6
1.6
0.37
0.59
MRUS51S
1.45
1.45
2.1
0.55
1.22
MRUS71D
1.8
1.5
2.7
0.8
2.16
MRSS32W
2.1
2.0
4.2
0.8
3.36
MRSS23E
2.8
2.9
8.1
1.1
8.93
MRSS22L-E
2.8
2.9
8.1
1.1
8.93
MRSS22L-E
MRSS23E
MRSS32W
Gnd
MRUS51S
MRUS61C
Out
1.0
1.45
1.8
2.1
1.6
Vcc
Out
Vcc
MRUS71D
Gnd
1.6
2.8
Wide
(mm)
1.6
2.0
2.9
Max0.8
1.45
1.1
1.5
Ｐage 10
© NEC Corporation 2007
Max0.8
Max0.55
0.02
0.35
Dual operating magnetic pole
•MR sensors can be operative against both North and South pole
Operating Magnetic Field
N
Ｐage 11
© NEC Corporation 2007
S
S
N
MR Sensor
MR Sensor
Operative
Operative
Low Source Supply
•Supply voltage for MRUS61C,MRUS51S, MRSS32W, and MRSS23E is
as low as 1.6V >>>>Contributed to low power consumption
MRUS61C
MRUS61C
MRUS51S
MRUS51S
MRUS71D
MRUS71D
MR
Sensor
MRSS32W
MRSS32W
MRSS23E
MRSS23E
MRSS22L-E
Asahi’s Hall IC
Hall
IC
Allegro’s Hall IC
1.6V 1.8V
2.5V
3.0V
Supply Voltage
Ｐage 12
© NEC Corporation 2007
3.5V
3.7V
Note: Asahi’s Hall IC : EW-6671,EW-6672 Allegro’s Hall IC : 3212
Summary –Performance Comparison
1.6
MRUS71D
Max0.55
1.17mm³
Output 1: 1.5mT(typ)2.5mT(max)
Out
Vcc
Max0 .8
Max0.8
2.16mm³
1.6
2.8
Out
2.0
1.5
0.59mm³
MRSS23E
Gnd
1.6
2.1
Vcc
1.45
Volume
MRSS32W
Gnd
1.8
0.02
0.35
MRUS51S
1.45
Package
(Unit: mm)
1.0
MRUS61C
2.9
1.1
3.36mm³
8.93mm³
2.0mT (Typ)2.5mT(Max)
1.7mT (Typ)-2.2mT(Max)
0.8mT (min)
0.5mT (min)
ON sensitivity of
Magnetic Field
1.7mT (Typ)2.5mT(Max)
1.5mT (Typ) 2.2mT(Max)
OFF sensitivity of
Magnetic Field
0.8mT (min)
0.5mT (min)
Ambient Temperature
-40 to 85 degree
-40 to 85 degree
-40 to 85 degree
-40 to 85 degree
-40 to 85 degree
Supply Current
3uA (Typ)
3uA (Typ)
3uA (Typ)
3uA (Typ)
3uA (Typ)
Supply Voltage
1.6V - 3.5V
1.6V - 3.5V
2.4V - 3.6V
1.6V - 3.5V
1.6V - 3.5V
Temperature Stability
(Range of sensitivity
shifted)
0.3mT – 0.5mT
0.3mT – 0.5mT
0.3mT or less
0.3mT – 0.5mT
0.3mT – 0.5mT
Ｐage 13
© NEC Corporation 2007
Output 2: 3.5mT(typ)4.5mT(max)
Output 1: 0.5mT(min)
Output 2: 2.2mT(min)
Professional Technical Support
• Technical support members are here to find out the best solution for customers.
Customer Request
Need to find out
---Ideal sensor selection and its position
---magnet size, material, and/or position
NEC Technical Support
Request
•Technical magnetic field simulation
Specific request
---want to control switching angel
---want to realize multi detection
---want to check influence of the
magnetic parts such as speaker,
receiver, hinge, etc.
Please provide
-structural drawing
-magnet info (size, material etc)
-actual sample of magnetic parts
Ｐage 14
© NEC Corporation 2007
•Manual evaluation using actual samples
Evaluation report sample
Feedback
MR Sensor Road Map
Intermittent switch circuit inside
Reduction
1.6mm
Size
Reduction
Advanced
Feature
(0.55mm thick)
(0.37mm thick)
MRUS51S
MRUS61C
2 Output
MRUS71D
CSP
Leadless Package
1.0mm
1.45mm
Size
&
Voltage
1.6V Operation
1.45mm
HiHi-speed Detection
Size
Reduction
Advanced sensitivity characteristic
Advanced temperature stability
Adjustable Sensitivity
Size
Reduction
MRUS52F
2006
2006
2007
2007
2008
2008
Advanced
Function
2.8 mm
2.9mm
Size
Reduction
Analogue out
(1.1mm thick)
MRSS21-E
Higher Performance &
Stabilization of the characteristic
Ｐage 15
© NEC Corporation 2007
PKG Height
Reduction
2009
2009
Market Share in Japan
•Market share in Japan is rapidly increasing.
>MR sensors almost dominate the market in Japan
Others
20%
NEC
MR Sensors
10%
Hall ICs
25%
Hall ICs
70%
Hall ICs & Others
10%
NEC
MR Sensorｓ
90%
Year 2005 ~ 2007
© NEC Corporation 2007
NEC
MR Sensors
70%
1st Half Year
2003
1st Half Year
2002
Ｐage 16
Others
5%
Facility for MR Sensor
•MR sensors are designed and manufactured at Otsuki Plant
•MR sensors are processed in a clean room
Ohtsuki plant（NEC Yamanashi）
ISO 9001, ISO14001,TL9000
Qualified
Ｐage 17
© NEC Corporation 2007
Major Customers
•We’ve
•We’ve been
been serving
serving over
over 50
50 customers
customers
Domestic/International Customers(Alphabetical Order)
・Aiptek
・Alcatel
・Amoi
・Arima
・Canon
・Casio
・CCI
・CEI
・Chicony
・Cingpang
Ｐage 18
© NEC Corporation 2007
・Curitel
・ECS
・Festo
・FIC
・Flectronics
・Foxconn
・Fujitsu
・Gateway
・Hisense
・Hitachi
・HP
・HTC
・JVC
・Kyocera
・Lenovo
・LG
・Longcheer
・Motorola
・NEC
・Nintendo
・Nokia
・Panasonic
・Pantech
・Quanta
・Samsung
・Sangfei
・Sanyo
・Sharp
・Simcom
・SMC
・Sony
・Sony Ericsson
・TCL&Alcatel
・Toshiba
・Uniwill
・Wistron
Advantage of MR Sensor
Comparison with Hall ICs
Directions of Operating Magnetic Field
MR Sensors
Hall ICs
Horizontal
Vertical
N
S
Operative
Hall IC
MR Sensor
S
N
Operative
MR Sensor
MR sensor detects
horizontal magnetic field
Ｐage 20
© NEC Corporation 2007
N
S
S
N
Hall IC
Advantage of Horizontal Magnetic Field
MR sensor is tolerant of misalignment at initial condition!
X direction Advantage
Z
Z
N
N
S
S
X
MR sensor
Y
X
Y
Hall IC
Gap(mm)
The Comparison of MR and Hall IC
AL X- direction
12
11
10
9
8
7
6
5
4
3
2
1
0
MR X- direction
-9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9
Distance(mm)
Ｐage 21
© NEC Corporation 2007
AS X- direction
Flexible Magnet Positions
Ｚ
MR Sensor
Ｚ
Ｚ
Hall IC
Ｚ
Magnet
Magnet
Magnet
Magnet
MR sensor
MR sensor
Ｘ
Ｘ
Hall IC
Hall IC
Ｘ
Ｙ
Ｙ
Ｙ
Ｙ
Top view
Top view
Flexible magnet position
© NEC Corporation 2007
Top view
Right Position
Left position
Ｐage 22
Ｘ
Magnet position is limited.
Magnet has to be
Above the sensor.
Operation Principle
MR Sensor
Hall IC
Magnetic Field
MR Elements
Horizontal magnetic field on the
surface of MR sensor is needed
for MR sensor operation.
Ｐage 23
© NEC Corporation 2007
Hall Element center
Hall IC cannot operate without
magnetic field applied through
the Hall element center.
Design Tolerance
•MR sensor can detect magnetic fields on two planes using one magnet
•Hall IC position is always limited on one plane
MR sensor
3-Dimension
Operative
Z
Y
X
N S
Hall IC
Operative
MR sensor
Ｐage 24
© NEC Corporation 2007
Avoid Damage to Magnetic Cards
Using same size magnet (MR/ Hall magnetization), analysis on the effect of leakage magnetic flux to
magnetic cards according to the distance from the magnet is made.
Card Type
(650 Oersted )
*Credit Cards
(Ref)→ Rail road pass 300 Oersted
*ATM Cards
MR magnetization 4.5*1.1*5.5 （magnetization direction5.5mm）
Magnet
Hall magnetization 5.5*4.5*1.1 （magnetization direction1.1mm）
Relative Output [%]
% in the graph below is relative output, which is remanent output after demagnetization( when output
before magnetization is 100%).
If the relative output is under 60%, magnetic flux leakage causes fatal damage to the data on the card.
100
90
80
70
60
50
40
30
20
10
0
Effect of Magnetic flux leakage to magnetic cards
MR Sensor VS Hall IC
MR
N
S
S
O.K
MR magnetization11
N.G
Hall magnetization
Hall
MR direction
Hall direction
1.5
Ｐage 25
N
© NEC Corporation 2007
1.75
2
Distance between card and magnet [mm] *Data provided by NEC Tokin Corporation.
Confidential Information