Specifications

Motor Control
Sensing motor speed, position, and movement
102 Maxim Industrial Solutions
Benefits
• High integration provides accurate
phase information for precise sensing
of rotor position
– Differential input stage provides
enhanced noise immunity
– Precision amplifier and comparator
allow small-signal detection
– Zero-crossing detection provides
accurate phase information
MAX9924–MAX9927
The MAX9924–MAX9927 VR, or magnetic coil, sensor interface
devices are ideal for sensing the position and speed of motor shafts,
camshafts, transmission shafts, and other rotating wheel shafts.
These devices integrate a precision amplifier and comparator
with selectable adaptive peak threshold and zero-crossing circuit
blocks that generate robust output pulses, even in the presence
of substantial system noise or extremely weak VR signals. The
MAX9924–MAX9927 interface to both single-ended and differential-
ended VR sensors.
Improve performance and reliability in motor applications with a differential VR
sensor interface
Simplified block diagram of the MAX9924 VR sensor interface to a motor.
μC
DIFFERENTIAL
AMPLIFIER
ADAPTIVE/MINIMUM
AND
ZERO-CROSSING
THRESHOLDS
INTERNAL/EXTERNAL
BIAS VOLTAGE
VR SENSOR
MOTOR BLOCK
MAX9924