MAX9924 MAXIM [Maxim Integrated Products], MAX9924 Datasheet
MAX9924
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MAX9924 Summary of contents
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... Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold General Description The MAX9924–MAX9927 variable reluctance (VR or mag- netic coil) sensor interface devices are ideal for position and speed sensing for automotive crankshafts, camshafts, transmission shafts, etc. These devices inte- ...
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... Operating Temperature Range .........................-40°C to +125°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C ) (Note 1) JC BIAS = +25°C.) (Note 2) A SYMBOL CONDITIONS V (Note 3) CC MAX9924/MAX9925 I CC MAX9926/MAX9927 V > 4.1V, step time for V CC UVLO 1µs IN+, IN- Guaranteed by CMRR ...
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... CC GND 50pF unless otherwise noted. Typical values are MIN MAX PARAMETER INPUT DIFFERENTIAL AMPLIFIER (MAX9924/MAX9926) Input Voltage Range Differential Common-Mode Rejection Ratio Input Resistance ADAPTIVE PEAK DETECTION Fixed and Adaptive Peak Threshold V Watchdog Timeout for Adaptive Peak Threshold ...
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... With INT_THRS = GND, auto peak- t detect is disabled, and EXT_THRS is SW active I Modes A1, B BIAS V Modes A1 +125°C BIAS A V Mode A2 (MAX9924/MAX9926) INT_BIAS = +125°C, unless otherwise noted. All temperature limits are guaranteed by design 2.5V 5V 1kΩ, C PULLUP PULLUP MIN TYP MAX 0.2 0.3 x ...
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... FREQUENCY (Hz) V AND V vs. TEMPERATURE -50 - 100 125 TEMPERATURE (°C) ADAPTIVE THRESHOLD vs. TEMPERATURE 400 350 300 250 200 150 100 P 1kHz IN 50 MAX9924 0 -50 - 100 125 TEMPERATURE (°C) 5 ...
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... CM 0 -50 - 100 125 TEMPERATURE (°C) OVERDRIVEN INPUT VOLTAGES (MAX9924) MAX9924 toc14 100μs/div INPUT SIGNAL vs. COUT WITH WATCHDOG TIMER EXPIRED MAX9924 toc12 COUT INPUT SIGNAL 5V V BIAS f = 5Hz IN 20ms/div DIRN OPERATION (MAX9924) MAX9924 toc15 200μs/div ...
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... Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold PIN MAX9924 MAX9925 MAX9926 MAX9927 1 1 — — — 3 — 3 — — — — — — — — 1 — — 2 — ...
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... Differential Input and Adaptive Peak Threshold V CC 100kΩ IN 100kΩ IN+ INTERNAL REFERENCE 2.5V BIAS 8 _______________________________________________________________________________________ 100kΩ OP AMP 100kΩ COMPARATOR BUFFER 30% PEAK DETECTOR V MIN THRESHOLD MODE LOGIC INT_THRS EXT Functional Diagrams V CC MAX9924 GND 65ms COUT WATCHDOG V CC 10kΩ MODE ZERO_EN LOGIC INT_THRS ...
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Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold IN+ BIAS BUFFER _______________________________________________________________________________________ Functional Diagrams (continued) OUT MAX9925 OP AMP COMPARATOR 30% PEAK DETECTOR V MIN THRESHOLD EXT V CC GND 85ms COUT ...
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Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold V CC 100kΩ IN1 100kΩ IN1+ INTERNAL REFERENCE 2.5V BIAS1 EXT1 V CC 100kΩ IN2 100kΩ IN2+ BIAS2 EXT2 10 ______________________________________________________________________________________ Functional Diagrams (continued) 100kΩ ...
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Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold V CC IN1 IN1+ BIAS1 BUFFER V CC IN2 IN2+ BIAS2 BUFFER ______________________________________________________________________________________ Functional Diagrams (continued) OUT1 MAX9927 OP AMP COMPARATOR 30% PEAK DETECTOR V ...
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... The MAX9926 and MAX9927 are dual versions of the MAX9924 and MAX9925, respectively. The MAX9926 also provides a rotational output that is useful for quadrature-connected VR sensors used in certain high-performance engines. ...
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... Figure 1. Adaptive Peak Threshold Operation ______________________________________________________________________________________ Modes A1 and A2 in the MAX9924–MAX9927 use an internal adaptive peak threshold voltage to trigger the output comparator. This adaptive peak threshold volt- age scheme provides robust noise immunity to the input VR signal, preventing false triggers from occurring due to broken tooth or off-centered gear-tooth wheel ...
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... The ESL of the capacitor dominates past the self-resonance frequency resulting in a rise in impedance at high frequencies. Bypass the power supply of the MAX9924–MAX9927 with multiple capacitor values in parallel to ground. The use of multiple values ensures that there will be multiple self-resonance frequencies in the bypass network, low- ering the combined impedance over frequency ...
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... Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold 10kΩ VR SENSOR 10kΩ 1kΩ 10μF || 0.1μF Figure 2. MAX9924/MAX9926 Operating Mode A1 10kΩ VR SENSOR 10kΩ Figure 3. MAX9924/MAX9926 Operating Mode A2 ______________________________________________________________________________________ IN+ 1nF COUT IN- MAX9924 MAX9926 BIAS 1kΩ + ZERO_EN ...
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... Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold 10kΩ VR SENSOR 10kΩ 1kΩ 10μF || 0.1μF Figure 4. MAX9924/MAX9926 Operating Mode B 10kΩ VR SENSOR 10kΩ 1kΩ 10μF || 0.1μF Figure 5. MAX9924/MAX9926 Operating Mode C 16 ______________________________________________________________________________________ Application Circuits (continued) IN+ ...
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Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold 10kΩ VR 1nF SENSOR 10kΩ 1kΩ 10μF || 0.1μF Figure 6. MAX9925/MAX9927 Operating Mode A 10kΩ VR 1nF SENSOR 10kΩ 1kΩ 10μF || 0.1μF Figure 7. MAX9925/MAX9927 Operating Mode ...
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Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold 10kΩ VR 1nF SENSOR 10kΩ 1kΩ 10μF || 0.1μF Figure 8. MAX9925 Operating Mode C 18 ______________________________________________________________________________________ Application Circuits (continued) OUT IN+ COUT IN- MAX9925 BIAS 1kΩ V +5V ...
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... IN AMP 100kΩ IN+ 100kΩ BANDGAP REFERENCE VOLTAGE = BUFFER 30% BIAS PEAK DETECTOR THRESHOLD MODE LOGIC *THE MAX9924 IS CONFIGURED IN MODE A2. INT_THRS EXT Typical Operating Circuit MAX9924 V PULLUP R PULLUP COUT 85ms COMPARATOR TPU WATCHDOG V CC 10kΩ ZERO_EN V ...
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... Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold TOP VIEW + IN_THRS1 1 EXT1 2 BIAS1 3 MAX9926 COUT1 4 COUT2 5 BIAS2 6 EXT2 7 INT_THRS2 8 QSOP TOP VIEW + IN+ 1 IN- 2 N.C. 3 MAX9924 BIAS 4 GND 5 μMAX 20 ______________________________________________________________________________________ IN_THRS1 16 IN1+ 15 IN1 ZERO_EN COUT1 12 DIRN COUT2 11 GND 10 IN2- 9 IN2+ INT_THRS2 10 ...
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Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold For the latest package outline information and land patterns www.maxim-ic.com/packages. PACKAGE TYPE 10 µMAX 16 QSOP ______________________________________________________________________________________ Package Information PACKAGE CODE U10-2 E16-1 α α DOCUMENT NO. ...
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Variable Reluctance Sensor Interfaces with Differential Input and Adaptive Peak Threshold For the latest package outline information and land patterns www.maxim-ic.com/packages. Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim ...