Giant Magneto Resistive Position Sensor GMR B6 Version 2.0 This angle sensor is based on the Giant Magneto Resistive (GMR) technology. It is outstanding for the huge tolerances it offers to the user in assembly. 2.9 ±0.1 1.1 max 0.6 +0.1 -0.05 5 4 1 2 3 0.35 ±0.15 0.2 0.1 max +0.1 0.3 -0.05 0.25 M B 1.2 3 3 4 R1 supply 5 (= 2) ground 1, 4 GMR bridge access GPW06957 Dimensions in mm OHS00429 6, 3 Type Marking Ordering Code GMR B6 B Q62705-K5004 Data Sheet A Directions of internal magnetization 0.5 0.45 R3 2/5 M 0.9 R4 1 0.20 Reflow soldering 0.8 0.3 Pin Configuration R2 10˚ max 6 0.08 ... 0.15 2.6 max 10˚ max A Applications • Rotation and linear sensing with large airgaps • Angle encoders • Contactless potentiometers • Incremental encoders 6 2˚ ... 30˚ 1.9 1.3 ±0.1 B 0.1 ±0.3 Features • GMR sensor in SMD package • Sensitive to the direction, not to the intensity of the magnetic field • Constant TC of basic resistance R and magneto resistance ∆R 1 2000-07-01 GMR B6 The GMR B6 is an angle sensor based on sputtered metallic multilayer technology. 4 resistors are monolithically integrated on 1 chip. They can be used as a fullbridge or, if 2 external resistors are added, as 2 halfbridges. The outstanding feature of this magnetic sensor is the fact, that it is sensitive to the orientation of the magnetic field and not to its intensity as long as the field is in a range between 5 … 15 kA/m. This means, the signal output of this sensor is independent of the sensor position relative to the magnet in lateral, axial or rotational direction in the range of several millimeters. Optimum results are achieved by using magnetic targets like permanent magnets or magnetic pole-wheels. There is no need for a biasing magnet! Due to the linear change of both, basic and field dependent part of the resistance vs. temperature, simple and efficient electronic compensation of TC (R, ∆R) is possible. AED02956 1 ∆R )/2] RO N GMR B6 Bridge Voltage [(VO ∗ S 0.5 V4 0 V1 -0.5 V1- V4 -1 0 90 180 270 Angle Deg 360 Figure 1 Output Voltage of Half Bridges (V1, V4) and Full Bridge (V4 - V1) as a Function of the Magnetic Field Orientation Data Sheet 2 2000-07-01 GMR B6 Maximum Ratings Parameter Symbol Value Unit Operating temperature TA Tstg V1 GthC A Hrot – 40 … + 150 °C – 50 … + 150 °C 7 V >4 mW/K < 15 kA/m Storage temperature Supply voltage Thermal conductivity Magnetic field1) 1) larger fields may reduce the magnetoresistive effect irreversibly Characteristics (TA = 25 °C) Parameter Symbol Value Unit Nominal supply voltage V1N R0 ∆R/R0 5 V > 700 Ω >4 % Basic resistance Magnetoresistive effect Hrot = 5 ... 15 kA/m Output signal fullbridge @ V1N = 5 V VOUT > 200 mV Offset voltage @ V1N = 5 V |V0| <8 mV Temperature coefficient of basic resistance TCR0 + 0.09 … + 0.12 %/K Temperature coefficient of magnetoresistance TC∆R – 0.12 … – 0.09 %/K Temperature coefficient of magnetoresistive effect TC∆R/R0 – 0.27 … – 0.23 %/K Application Hints The application mode of the GMR position sensor is preferably as a bridge or halfbridge circuit. In every case this type of circuit compensates for the TC of the resistance value R0. To compensate for the TC of the GMR effect ∆R/R0, if there is the necessity, is left to the application circuit and can be done for example with a NIC circuit. When operated over a complete 360° turn, a total signal of ≈ 20 mV/V is achieved at 25 °C with a halfbridge. The output signal is doubled to of ≈ 40 mV/V when a fullbridge circuit is used. In the case of linear position sensing, the electrical circuit remains unchanged. Data Sheet 3 2000-07-01 GMR B6 Output Voltage Degradation (typical) at high Temperature Operation 100 % Magnetoresistive Effect (typical) versus Temperature ∆R/R0 = f(TA) AED02953 TA = 105 ˚C TA = 125 ˚C % 110 Magnetoresistive Effect (normalized) 99 Output Voltage (normalized) AED02959 120 98 97 96 100 90 80 70 TA = 150 ˚C 95 2 10 103 Operation Time 60 -50 h 104 -10 30 70 110 ˚C 150 T Basic Resistance (typical) versus Temperature R0 = f(TA) 120 AED02954 Resistance (normalized) % 110 100 90 80 -40 -20 0 20 40 60 80 100 ˚C 150 T Data Sheet 4 2000-07-01