MAX9924MAX9927 19-4283 Rev 4 3/12 Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold General Description Features The MAX9924MAX9927 variable reluctance (VR or mag- Differential Input Stage Provides Enhanced Noise netic coil) sensor interface devices are ideal for position Immunity and speed sensing for automotive crankshafts, Precision Amplifier and Comparator Allows camshafts, transmission shafts, etc. These devices inte- Small-Signal Detection grate a precision amplifier and comparator with selectable adaptive peak threshold and zero-crossing circuit blocks User-Enabled Internal Adaptive Peak Threshold or that generate robust output pulses even in the presence Flexible External Threshold of substantial system noise or extremely weak VR signals. Zero-Crossing Detection Provides Accurate The MAX9926/MAX9927 are dual versions of the Phase Information MAX9924/MAX9925, respectively. The MAX9924/ MAX9926 combine matched resistors with a CMOS input Ordering Information precision operational amplifier to give high CMRR over a wide range of input frequencies and temperatures. The PART TEMP RANGE PIN-PACKAGE MAX9924/MAX9926 differential amplifiers provide a fixed -40C to +125C gain of 1V/V. The MAX9925/MAX9927 make all three ter- MAX9924UAUB+ 10 MAX minals of the internal operational amplifier available, -40C to +125C MAX9924UAUB/V+ 10 MAX allowing greater flexibility for gain. The MAX9926 also -40C to +125C MAX9925AUB+ 10 MAX provides a direction output that is useful for quadrature- -40C to +125C MAX9926UAEE+ 16 QSOP connected VR sensors that are used in certain high-per- MAX9926UAEE/V+ -40C to +125C 16 QSOP formance engines. These devices interface with both new-generation differential VR sensors as well as legacy MAX9927AEE+ -40C to +125C 16 QSOP single-ended VR sensors. MAX9927AEE/V+ -40C to +125C 16 QSOP The MAX9924/MAX9925 are available in the 10-pin +Denotes a lead(Pb)-free/RoHS-compliant package. MAX package, while the MAX9926/MAX9927 are /V denotes an automotive qualified part. available in the 16-pin QSOP package. All devices are specified over the -40C to +125C automotive temper- ature range. Applications Camshaft VRS Interfaces Crankshaft VRS Interfaces MAX is a registered trademark of Maxim Integrated Products, Inc. Vehicle Speed VRS Interfaces Simplified Block Diagram ENGINE BLOCK MAX9924 DIFFERENTIAL VR SENSOR AMPLIFIER C ADAPTIVE/MINIMUM AND ZERO-CROSSING THRESHOLDS INTERNAL/EXTERNAL BIAS VOLTAGE Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold ABSOLUTE MAXIMUM RATINGS V to GND.............................................................-0.3V to + 6V Operating Temperature Range .........................-40C to +125C CC All Other Pins..............................................-0.3V to (V + 0.3V) Junction Temperature......................................................+150C CC Current into IN+, IN-, IN +, IN -.......................................40mA Storage Temperature Range .............................-65C to +150C Current into All Other Pins ................................................20mA Lead Temperature (soldering, 10s) .................................+300C Output Short-Circuit (OUT , OUT) to GND.............................10s Soldering Temperature (reflow) .......................................+260C Continuous Power Dissipation (T = +70C) (Note 1) A 10-Pin MAX (derate 8.8mW/C above +70C) ........707.3mW 16-Pin QSOP (derate 9.6mW/C above +70C)........771.5mW Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. PACKAGE THERMAL CHARACTERISTICS (Note 1) MAX QSOP Junction-to-Ambient Thermal Resistance ( ) ......113.1C/W Junction-to-Ambient Thermal Resistance ( ) ......103.7C/W JA JA Junction-to-Case Thermal Resistance ( ) ................42C/W Junction-to-Case Thermal Resistance ( ) ................37C/W JC JC Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial. ELECTRICAL CHARACTERISTICS (V = 5V, V = 0V, MAX9925/MAX9927 gain setting = 1V/V, Mode A1, V = 2.5V, V = 5V, R = 1k , C = CC GND BIAS PULLUP PULLUP COUT 50pF. T = T to T , unless otherwise noted. Typical values are at T = +25C.) (Note 2) A MIN MAX A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS POWER SUPPLY Operating Supply Range V (Note 3) 4.5 5.5 V CC MAX9924/MAX9925 2.6 5 Supply Current I mA CC MAX9926/MAX9927 4.7 10 V > V = 4.1V, step time for V CC UVLO CC Power-On Time P 30 150 s ON ~ 1s INPUT OPERATIONAL AMPLIFIER (MAX9925/MAX9927) Input Voltage Range IN+, IN- Guaranteed by CMRR 0 V V CC Temperature drift 5 V/C Input Offset Voltage V OS-OA 0.5 3 mV Input Bias Current I (Note 4) 0.1 6 nA BIAS Input Offset Current I (Note 4) 0.05 2 nA OFFSET Common-Mode Rejection Ratio CMRR From V = 0 to V 75 102 dB CM CC MAX9925 88 105 Power-Supply Rejection Ratio PSRR dB MAX9927 77 94 Output Voltage Low V I = 1mA 0.050 V OL OL V - CC Output Voltage High V I = -1mA V OH OH 0.050 To 1% of the actual V after output OUT Recovery Time from Saturation t 1.2 s SAT saturates Gain-Bandwidth Product GBW 1.4 MHz Slew Rate SR 2.3 V/s Charge-Pump Frequency f 1.3 MHz CP 2 MAX9924MAX9927