High Sensitivity Low Power TMR Switch Position Sensing > LF22214TMR TMR Omni-polar Switch 14 Gauss 1.5uA Open Drain Sensor Description The LF22214TMR 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 open drain 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 1.5A (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 LF22214TMR switches low (turns on) when the Osc and Vcc Duty Control Logic magnetic field parallel to the sensing axis exceeds the operate point threshold, Power regulator with temperature B . When the magnetic field is reduced below the release point B device compensation OP RP output switches high (turns off). The difference between the B and the B is OP RP Vout the hysteresis B of the device. H Offset TMR Driver Sensor cancellation Features GND Tunneling Magnetoresistance (TMR) High frequency up to 1kHz technology GND Operation with north or south Pole Low power consumption at 1.5A 1.8V to 5.5V operating range X axis sensing direction TMR Switch Typical Applications Circuit Benefits Low switching points for high Wider airgap capability sensitivity Operates with smaller magnets for Vcc Excellent thermal stability cost reduction 1K High tolerance to external magnetic RoHS compliant Vcc field interference TMR Out 0.1F Out Applications GND Proximity detection High speed sensing Utility meters including gas, water, Low power applications electric and heat meters Rotary sensing GND Output Behavior Versus Magnetic Pole Note: It is strongly recommended that an external bypass capacitor be connected in-close- proximity to the device between the supply and ground pins to reduce noise. The recommended Parameter Test Conditions Output (volts) 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: When power is turned on under Zero magnetic field, the output is High. 2020 Littelfuse Revised: 01/10/20 littelfuse.com Specifications are subject to change without notice.High Sensitivity Low Power TMR Switch Position Sensing > LF22214TMR 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 20 mA OUTSINK B Magnetic Flux Density 2800 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 3.0 5.5 V Operating CC V Output Stress Voltage 5.5 V stress Output = High,V = 3V, cc I (average) Output leak current 1 A leak V = 3V out V OH Output High Voltage Vcc -0.2 Vcc V Pull-up Resistance = 1Kohm R off Output turn-off Resistance 10 M Output = High R on Output turn-on Resistance 10 Output = Low Output = Low, V = 3V, cc V OL Output Low Voltage 0 0.1 V I = 3mA sink I Supply Current 1.5 A Output Open CC Freq Response Frequency 1.0 kHz Magnetic Characteristics ( TA = +25C, Vcc = 3.0V) Symbol Characteristics Min. Typ. Max. Unit B 8 14 25 Gauss OPS Operation Point B OPN -25 -14 -8 Gauss B 5 10 20 Gauss RPS Release Point B -20 -10 -5 Gauss RPN B Hysteresis -- 4 -- Gauss H 2020 Littelfuse Revised: 01/10/20 littelfuse.com Specifications are subject to change without notice.