The MLX90217 self adjusting digital output rotary position gear tooth sensor is designed for use in automotive camshaft sensing as well as other speed sensing applications. It is designed to be used with a bias magnet south facing the back (non marked) side of the IC. The device has an open collector output which is short circuit protected. The MLX90217 is a sophisticated IC featuring an on chip 10 bit A/D Converter and logic that acts as a digital sample and hold circuit. A separate 4 bit A/D converter provides a fixed hysteresis. The 90217 does not have a chopper delay. The 90217 uses a single Hall plate which is immune to rotary alignment problems. The bias magnet can be from 50 to 400mT. As the signal is sampled, the logic recognizes an increasing or decreasing flux density. The output will turn on (BOP) after the flux has reached its peak and decreased by an amount equal to the hysteresis. Similarly the output will turn off (BOP) after the flux has reached its minimum value and increased by an amount equal to the hysteresis.
The MLX90217 is a self‑adjusting Hall‑Effect cam sensor designed for automotive camshaft and speed‑sensing applications. It features an on‑chip 10‑bit A/D converter, short‑circuit‑protected open‑collector output, and operates over a wide temperature range (‑40 °C to 150 °C).
The document provides detailed electrical and magnetic specifications, performance graphs, recommended wiring circuits, physical dimensions, reliability information and handling precautions for designers integrating the sensor into their systems.
| Supply Voltage (Voo) Operating Range | 3.5 V – 24 V |
|---|---|
| Supply Current (typ) at 12 V | 3.0 mA |
| Supply Current (typ) over 3.5‑24 V | 1 mA – 6 mA |
| Leakage Current | 10 pA |
| Maximum Output Current | 25 mA |
| Output Saturation Voltage (Vsat) at 12 V, 25 mA | 600 mV |
| Output Short‑Circuit Current | 150 mA |
| Clock Frequency (max) | 800 kHz |
| Bandwidth (max) | 15 kHz |
| Back Bias Range | -30 mT – 400 mT |
| Linear Region Magnetic Range | 50 mT – 500 mT |
| Hysteresis | 10 mT (max) |
The sensor operates from 3.5 V up to 24 V.
It has an open‑collector output that is short‑circuit protected.
The output can source up to 25 mA.
A Zener diode can be used to clamp positive spikes and Schottky diodes to clamp negative excursions.