Automotive Sensors with TMR Technology - Mouser Electronics · 2017-03-16 · 1 Automotive Sensors...

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Automotive Sensors with TMR Technology International Automotive Electronics Conference Electronica Shanghai 15 March 2017

2 Confidential and Proprietary | Littelfuse, Inc. © 2017 2 Confidential and Proprietary | Littelfuse, Inc. © 2017

Agenda 议程 History of Magnetic Sensors 磁性传感器的历史 Why do we select TMR? 为什么力特选择TMR技术

– Hall Sensors 霍尔传感器 – Magneto Resistive Sensors 磁阻传感器

Anisotropic Magneto-resistive (AMR) 各向异性磁阻传感器 Giant Magneto-resistive (GMR) 巨磁阻传感器 Tunnelling Magneto-resistive (TMR) 隧道磁阻传感器

– Why do we select TMR? 为什么力特选择TMR技术

LF TMR Sensor 力特TMR传感器 – TMR Level Sensors TMR液位传感器 – TMR Buckle Sensors TMR安全带锁扣传感器 – TMR Current Sensors TMR电流传感器

Summary 总结


History of Magnetic Sensors 磁性传感器的历史 1857 William Thompson (Lord Kelvin) discovered the Anisotropic Magneto-resistive effect (AMR ), It

didn’t find application until 1980s.

1857 1857年Thompson在铁磁多晶体中发现了各向异性磁阻现象，直到1980年AMR效应才被应用到磁盘磁头

1879 Edwin Hall discovered that semiconductor could be used to detect magnetic fields. The phenomena was named after him “the Hall effect” again the technology didn’t become commercially available until 1970s.

1879 1879年美国物理学家Hall首次发现该现象，但其真正商业应用要推迟到上世纪70年代

1988 Peter Grunberg and Albert Fert independently discovered the Giant Magneto-resistive effect (GMR). In 2007 they received a Nobel prize for the discovery. Found immediate application in hard disc drive.

1988 1988年德国尤利希科研中心的物理学家格伦贝格及巴黎南大学物理学家费尔独立发现巨磁阻现象。

该发现于上世纪90年代给硬盘行业带来一场革命

1994 Jagadeesh Moodera and his research group discovered the Tunnelling Magneto-resistive effect (TMR) Used by Seagate in hard drives.

1994 尽管Michel Julliere于1975年发现低温隧道磁阻现象，但是直到 1994年美国物理学家Moodera及其

团队发现室温下隧道结磁阻，以至于后来被希捷公司用于硬盘磁头

Jagadeesh Moodera

Peter Gruberg

Albert Fert

Edwin Hall

Lord Kelvin


Hall Effect 霍尔传感器

Hall sensors use the Hall principle of applied current x direction resulting in the voltage in Y direction where X and Y are perpendicular

霍尔传感器基于霍尔原理。当给电流外加一个垂直磁场B，

会在材料Y方向产生霍尔电压

The signal is very small so could not be utilised until the development in semiconductor technologies

霍尔效应信号十分微弱，但随着半导体材料、制造工艺和

集成电路技术的发展，霍尔传感器获得了长足发展

A very common technology, but consumes current to develop the Hall voltage

霍尔技术应用非常普遍，但其功耗相对较高

B

Hall voltage developed

I Magnetic Field

X Y


Magneto-Resistive Sensors 磁阻传感器 Magneto-resistive (MR) sensors have in common that the electrical

resistance of the sensor changes due to the influence of a magnetic field 磁阻传感器是感测外磁场作用下材料的电阻变化

This phenomenon results from the fact that electrons have spin and

create the magnetic field which means that they become aligned to any external magnetic field

该现象主要源于电子的自旋产生磁场，当受到外界磁场的影响而变得排列有序

The alignment of the spin of the electrons effects the ease of which the

electrons can flow though a conductor or barrier 排列有序的旋转电子使得其穿过导体或隔离层更加容易

Easy flow lowers the resistance 顺畅的载流从而降低了电阻值


Anisotropic Magneto Resistive – AMR 各向异性磁阻传感器 Resistance varies depending on direction of the magnetic field 磁阻的变化取决于磁场和电流间夹角 Relatively Low Resistance, High R Large size higher cost AMR相对其它磁阻技术电阻变化较低

Effect on the order of DR/R0 ≈ 3% AMR灵敏度约为3%

Can outperform hall for sensitivity and performance but more expensive AMR灵敏度及性能优于霍尔技术，但是同等条件下价格更贵 Used for wheel speed sensors in automotive AMR目前主要用于汽车轮速传感器 Magnetization rotates in response to applied field H 当外部磁场H方向变化时，磁体的内建磁场M方向也会发生变化 R varies as a function of the angle θ, between the direction of current flow

and the magnetization 电阻R随着电流方向与磁化方向的夹角θ而变化


Giant Magneto Resistive – GMR 巨磁阻传感器 GMR sensor is constructed as a sandwich of layers of ferromagnetic

metals separated by a non-magnetic conductor GMR传感器如同三明治结构，铁磁金属/非磁性金属/铁磁金属构成的多层膜 When no magnetic field is applied, the spin vectors in the opposite

ferromagnetic materials are anti-parallel 当未施加外加磁场时，在上下两层铁磁材料中的自旋矢量反平行分布 The strong scattering of the conduction electrons results in a high

resistance 两种自旋状态的传导电子都在穿越与其自旋方向相反的磁层处受到强烈的散

射作用，器件呈现高阻态 Less scattering of the conduction electrons when the spin vectors are

parallel (Low resistance) 反之，当相邻磁矩平行分布，自旋的传导电子可以在晶体内自由移动，散射

不明显，器件呈现低阻态 Effect is the order of ᐃR/R < 20% GMR的灵敏度最多可以达到20% R varies as a function of the angle θ, between the direction of the

magnetization in adjacent layers 电阻R随着相邻层磁化方向的夹角θ变化而变化


Tunnelling Magneto Resistive – TMR 隧道磁阻传感器 TMR sensors have a minimum of 1 insulating layer sandwiched between 2

ferromagnetic layers TMR是和GMR类似的三明治结构，感应元件的势垒层被铁磁性材料的自由层及钉扎

层夹在中间 The layers are very thin approximately 0.1 to 100 nm 各薄膜层的典型厚度大约在0.1到100纳米之间 The conduction method is by quantum tunnelling of the electrons through the

insulating barrier 电子传导是通过量子隧穿效应穿过势垒层 The spin orientation of the electrons in one of the Ferromagnetic layers are pinned

using a permanent magnet layer 钉扎层的磁矩由于受到永磁体磁场作用是相对固定的 The spin of the orientation of electrons in the other Ferromagnetic layer can rotate

in response to a applied magnetic field 但是自由层的磁矩是相对自由且可旋转的，随外场的变化而发生翻转 As the spin orientation aligns more electrons can tunnel through the barrier

reducing the resistance 当自由层与钉扎层磁矩逐渐接近平行时，电子隧穿变得容易，从而电阻降低 The effect of the resistance change can be up to 100% 电阻变化率可以达到100%


Comparison of Different Technologies 不同技术的对比

Technology 技术 Hall Effect AMR GMR TMR

Power Consumption (mA) 功耗

5~20 1~10 1~10 0.001~0.01

Field Sensitivity(mV/V/Oe) 灵敏度

~0.05 ~1 ~3 ~100

Dynamic Range (Oe) 动态响应范围

~10000 ~10 ~100 ~1000

Resolution (nT/Hz ½) 分辨率

>100 0.1~10 1~10 0.1~10

Temperature Performance (°C) 工作温度范围

<150 <150 <150 <200

Air gap (Maximum mm) 气隙

3.5-4.0 5.0-5.5

TMR has predominant advantage over Hall and earlier MR technologies TMR在性能方面占据绝对优势 Lower cost magnet design TMR对磁铁材料要求相对较低


LF Automotive Applications of Magneto Resistive sensors 力特磁阻传感器应用 Fluid level measurement 液位检测

– Engine coolant fluid 发动机冷却液液位

– DEF (Urea Solution) 尿素液液位 Wheel speed sensors 轮速传感器 Gear shift angle position measurement 变速箱档位角度检测 Linear displacement measurement 线性位移检测

– Fork position 拨叉位置 – Seat track position 座椅位置

Safety belt buckle sensor 安全带锁扣传感器

Current measurement 电流检测


TMR Level Sensors TMR液位传感器 Current automotive level sensor industry is mainly using reed switch which has below disadvantages: 目前汽车液位传感器行业主要采用干簧管技术，但干簧管技术有如下不足： - Inconsistency on/off performance piece by piece 件与件之间的开关性能差异 - Higher cost of SMT type reed switch considering additional cost of cutting and forming SMT类型的干簧管由于需要剪切、弯折引脚，其成本相对较高 - Higher transition time of reed switch and fragile glass capsule 干簧管切换时间较长且玻璃管容易破裂 While TMR can solve the issues specific for automotive 但是TMR解决了干簧管在汽车应用上的弊端

Reed Ladder 干簧管递进式

TMR Ladder TMR递进式

Reed switches (Mechanical switch, passive device)

TMR switches (Electrical switch, active device)


TMR vs Reed Technology Level Sensors TMR和干簧管技术对比

Characteristic 项目 Reed Switch Level Sensor 干簧管式液位

TMR Switch Level Sensor TMR式液位

Input voltage range 输入电压范围

System Voltage 系统电压 5 ±0.5 Vdc

Output Type 输出信号类型

Resistance or Voltage 电阻输出或电压输出

Voltage 电压

Current consumption 功耗 Zero Max. 3.0uA

Transition time 电平切换时间 ○ +

Cost (high volume)

成本 ○ +


Overview of Safety Products 安全类产品概要

DA

B

PAB

AC

U

Seat Belt Buckle Sensor 安全带锁扣传感器

Seat Belt Tension Sensor 安全带张紧力传感器

Seat Track Position Sensor 座椅位置传感器

Airbag Control Unit


TMR Safety Sensors TMR安全类传感器

• Buckle unfastened • Switch closed

• Buckle fastened • Switch open

LF has a full range of technologies and solutions for seatbelt buckle detection and belt tension sensing. TMR’s introduction allows maximum design freedom for best solution

力特具备各类安全带锁扣传感器技术，TMR技术的引入给客户提供多样化的选择

As non-contact presence sensing, TMR results in robust, long life sensors

作为非接触式传感器，TMR技术更加可靠耐用 TMR requires smaller magnet to activate the sensor which

means a lower cost solution TMR相对其它技术所需磁铁尺寸更小也更便宜

Buckle Switch

锁扣开关 Belt Tension Sensing

安全带涨紧力传感

Hall Effect Hall Effect

TMR TMR

Mechanical


TMR Current Sensor TMR电流传感器

Overview of Current Sensor Applications: 电流传感器应用概要：

Battery sensor for Start-stop system monitoring and 12V battery: 启停系统及12V电池监控

- Monitoring of Battery charges/discharges - State of Charge (SoC) 监控电池充放电-健康状态

- Early battery faults indication - State of Health (SoH) 电池早期失效预防-电池健康状态

- Cranking capability - State of Function (SoF) 启动能力-功能状态

Automotive HEV inverters: Over current and short circuit protection 新能源汽车逆变器过载及短路保护

Motor protection: Over current and short circuit protection 电机过载及短路保护


TMR Current Sensors vs Shunt Technology TMR与精密电阻技术比较

Characteristic 项目 Shunt 精密电阻 TMR

Contactless Sensing 非接触传感 No Yes

AC/DC Measurement 交流/直流检测 DC Only AC & DC

Measurement Accuracy 测量精度 ○ +(low)

Power consumption 功耗 ○ + Noise(low current) 噪声 ○ +


Summary 总结

As a leading technology company, Littelfuse is working toward incorporating TMR into our portfolio of sensor applications.

作为技术导向型公司，力特正在各个领域导入TMR技术

All traditional Hall/reed applications can be replaced by TMR. 所有传统霍尔、干簧管类应用均可以被TMR技术替代

As the 3rd generation of MR, TMR will become the predominant MR technology in the near future.

作为第三代MR技术，TMR必将在不久的将来成为主流技术

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Automotive Electronics Solutions for More Comfortable and Saver Driving


Agenda

Automotive Over-Voltage Protection Automotive Over-Current Protection Automotive Power Summary


Automotive Over-Voltage

Protection

21 Proprietary to Littelfuse. Littelfuse, Inc. © 2017

Littelfuse ESD Protection Portfolio Littelfuse offers three ESD protection technologies

Multi Layer Varistors (MLV)

Ceramic based

TVS Diode Arrays (SPA)

Silicon based (semiconductor)

Xtreme-Guard (XGD)

Polymer based


Littelfuse Offers Three ESD Protection Technologies From low cost to high frequency

Technology Data Rate Relative Cost Typical Applications Main Advantage

MLV Ceramic

Up to 125 Mbps

Best

Keypad Switch Audio Analog video USB 1.1 RS232

Lowest cost Broad discrete offering

AEC-Q200

SPA Silicon

Up to 5 Gbps

Good

USB 2.0 USB 3.0

1394 HDMI

Ethernet MMC interface LCD module

Lowest RDYN For lower clamping voltage range

AEC-Q101

XGD Polymer

More than 10 Gbps

Good RF antenna Lowest capacitance

For highest data rates AEC-Q200


MLA Automotive Series offers best flexibility by its Scalability over a wide operating range VM(DC) = 3.5V to 48V Different leadless 0603, 0805, 1206 and 1210 packages Robustness even in harsh automotive environments

All MLA products out of Dongguan Fab are - AEC-Q200 - RoHS compliant - HAL-free

Examples of success stories with varistors in automotive

Infotainment - ESD protection with

V18MLA0603NHAUTO

Car Lighting - ESD protection with

V18AUMLA1210H

Keyless Entry - ESD protection with

V18AUMLA1206H

Multi Layer Varistors (MLV) ESD Protection for Automotive Electronics according to IEC 61000-4-2


AQ, SM and SD Automotive Series offer protection for data lines against ESD, EFT and lightning surges Uni- and bidirectional devices with leakage current < 100nA ESD absorption capability of up to±30kV for up to 4 channels Low loading capacitance for high data rates of USB, GPS, LTE and

many more

All AQ products are AEC-Q101 RoHS compliant HAL-free

SD24C-01FTG

SM24CANA-02HTG

SESD – Ultra low capacitance targeted for high speed circuits (Bluetooth, GPS, LTE, USB 3.0,…)

TVS Diode Arrays (SPA®) ESD Protection for Communication Buses according to ISO 10605


XTREME-GUARD Series protects sensitive electronics against extreme ESD conditions Ultra-low capacitance of 0.04 / 0.09 pF allows for distortion-free

protection of high speed data and RF High operating temperature of up to 125ºC Used for RF applications such as USB, HDMI, Ethernet, Industrial

and Automotive Antenna Systems

Shark fin GPS antenna protection

All XGD parts are - RoHs compliant - HAL-free - AEC-Q200

Xtreme-Guard (XGD) ESD Protection for High Speed Communication according to IEC 61000-4-2

Success Story


Littelfuse Surge Protection Portfolio

Littelfuse offers three Surge Protection Technologies Metal Oxide Varistors (MOV)

Ceramic based

TVS Diode Arrays (SPA)


TVS Diodes



Application: Engine Cooling Valve Transient voltage suppression for inductive loads

Cooling Valve

Control Unit

+Vbat

GND

Semiconductor Overvoltage Protection

AUMOV protects semiconductor element during Switch-off phase from inductive spikes generated by valve coil.


TVS Diodes – Manufactured by Littelfuse Wafer fab and backend assembly located in Wuxi, China

ISO 14000 AS9100 (for Aero) ISO/TS 16949 Manufacturing of – TVSs – Thyristors – SIDACtors

Output > 34k wafers/week

Employees > 1,100

Wafer FABAssembly & Testing

Technical Center


Littelfuse TVS Diodes Automotive product series (AEC-Q101)

Littelfuse Series Acquired Series Package Directional Power rating (by 10x1000µs)

Reverse Standoff Voltage (VR)

TP6KE DO-15 Uni & Bi 600W 11-78

TPSMF4L SZSMF ( 200W) SOD-123FL Uni 400W

5-85

SZ1SMA DO-214AC Uni & Bi 5-85

TPSMA6L DO-221AC Uni 600W

5-85

TPSMB SZ1SMB/SZP6SMB DO-214AA

Uni & Bi

6 -78

TP1.5KE DO-201 1500W

11-78

TPSMC SZ1.5SMC DO-214AB 10.2-78

TPSMDJ DO-214AB 3000 W 10-43

SLD8S ( NEW! ) SMTO-263 6600 W

10-57

SLD P600 10-60

SLD and SLD8S are specially designed for Load Dump applications ISO 7637-2 5a/b ISO 16750-2 5a/b


Automotive Over-Current

Protection


Where Is Resettable and Non-Resettable Over-Current Protection Used?

Resettable Small and Medium Powered Motors Interfaces

Non-Resettable Electric and Hybrid Drives Internal Combustion Engine Applications

BATTERY MANAGEMENT

SYSTEM

IGNITION COILS

DASHBOARD ELECTRONICS

BACKUP CAMERA

BODY CONTROL MODULE

DASHBOARD ELECTRONICS


Application Example Battery Management System


Automotive Power


Ignition System — Coil-on-Plug

Ideal for coil−on−plug applications

High Collector−to−Emitter avalanche energy

Over−Voltage clamped protection

Gate−Emitter ESD Protection

Higher collector current capabilities

Lower saturation voltage

DPAK and D2PAK packages

Wafers and dice available for module integration

A broad and very representative portfolio covering the requirements and following the market trends


Output rectifier in SMPS – Up to 200V (40V – 200V) and 15A (5A-15A) – Trench-MOS design: Lower VF than conventional MBR Schottky – DC-DC converter in automotive application – AEC-Q101/ Wafer FAB & Assembly site ISO/TS16949 certified

Schottky Barrier Rectifier

D-PAK replacement with smaller package

DST5100S-A (5A, 100V, TO-277B)


Summary The number of electronic systems in automobiles constantly increases. So protection

needs to be considered early in the design phase to ensure most effective treatment. Littelfuse has more than 80 years of experience in the automotive industry and a

leading positon in circuit protection. One-stop shop for circuit protection. The latest acquisitions and investments Littelfuse has made align with its strategy to

expand in power semiconductor applications and automotive electronics market while strengthening its core circuit protection business.


Control

Sense

Protect

Automotive Sensors with TMR Technology - Mouser Electronics · 2017-03-16 · 1 Automotive Sensors...

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Transcript of Automotive Sensors with TMR Technology - Mouser Electronics · 2017-03-16 · 1 Automotive Sensors...