High Sensitivity Ultra Low Power TMR Switch Position Sensing > LF21115TMR TMR Omni-polar Switch 17 Gauss 200nA Push Pull Sensor Description The LF21115TMR TMR Switch is a digital omni-polar magnetic switch that integrates TMR and CMOS technology in order to provide a magnetically triggered digital switch with high sensitivity, high speed, and low power consumption. It contains a TMR magnetic sensor and CMOS signal processing circuitry within the same package, including an on-chip TMR voltage generator for precise magnetic sensing, a TMR voltage amplifier and comparator plus a Schmitt trigger to provide switching hysteresis for noise rejection, CMOS push-pull output and X axis sensing direction. An internal band gap regulator is used to provide a temperature compensated supply voltage for internal circuits, permitting a wide range of supply voltages. It draws only 200nA (see Features below) resulting in low power operation, additionally it has fast response, accurate switching points, excellent thermal Functional Block Diagram stability, and immunity to stray field interference. It is available in the SOT23-3 package. The output of the LF21115TMR switches low (turns on) when the Vcc Power regulator magnetic field parallel to the sensing axis exceeds the operate point threshold, with temperature compensation B . When the magnetic field is reduced below the release point B device OP RP output switches high (turns off). The difference between the B and the B is OP RP the hysteresis B of the device. H Offset TMR Latch Vout cancellation Sensor Features X axis sensing direction Tunneling Magnetoresistance (TMR) High frequency up to 50Hz technology Operation with north or south pole GND Ultra low power consumption at 1.8V to 5.5V operating range 200nA Benefits TMR Switch Typical Applications Circuit Low switching points for high Wider airgap capability sensitivity Operates with smaller magnets for Excellent thermal stability cost reduction High tolerance to external magnetic RoHS compliant Vcc field interference Vcc TMR Out 0.1F Applications Out Proximity detection Speed sensing GND Utility meters including gas and Battery powered applications water meters Rotary sensing Output Behavior Versus Magnetic Pole GND Note: It is strongly recommended that an external bypass capacitor be connected in-close- Parameter Test Conditions Output (volts) proximity to the device between the supply and ground pins to reduce noise. The recommended value for the external bypass capacitor is 0.1F. B > B Low (On) OPS South Pole 0 < B < B High (Off) RPS B < B Low (On) OPN North Pole 0 > B > B High (Off) RPN Note: The output is High when power is turned on under zero magnetic field. 2020 Littelfuse Revised: 01/10/20 littelfuse.com Specifications are subject to change without notice.High Sensitivity Ultra Low Power TMR Switch Position Sensing > L211115TMR Absolute Maximum Ratings ( TA = +25C, unless otherwise specified) Symbol Characteristics Values Unit V Supply Voltage 7.0 V CC V Reverse Supply Voltage 0.3 V RCC I Output Current 9.0 mA OUTSINK B Magnetic Flux Density 4000 Gauss V ESD level(HBM) 4 kV ESD T Operating Temperature -40 ~ 125 C A T Storage Temperature -50 ~ 150 C stg Note: Stresses greater than the Absolute Maximum Ratings specified above may cause permanent damage to the device. These are stress ratings only functional operation of the device at these or any other conditions exceeding those indicated in this specification is not implied. Device reliability may be affected by exposure to absolute maximum rating conditions for extended periods of time. Electrical Characteristics ( TA = +25C, Vcc = 3.0V) Symbol Characteristics Min. Typ. Max. Unit Conditions V Supply Voltage 1.8 3 5.5 V Operating CC V OH Output High Voltage Vcc -0.3 V V OL Output Low Voltage 0.2 V I Supply Current 200 nA Output Open CC Freq Response Frequency 50 Hz Magnetic Characteristics ( TA = +25C, Vcc = 3.0V) Symbol Characteristics Min. Typ. Max. Unit B 9 17 26 Gauss OPS Operation Point B -26 -17 -9 Gauss OPN B RPS 5 12 20 Gauss Release Point B -20 -12 -5 Gauss RPN B Hysteresis 5 Gauss H 2020 Littelfuse Revised: 01/10/20 littelfuse.com Specifications are subject to change without notice.