Miniature Absolute Magnetic Shaft Encoder

May 17, 2007
The MA3 is a miniature absolute magnetic shaft encoder that provides shaft position information over 360° of rotation with no stops or gaps. The MA3 is available in two output versions, analog and pulse width modulation (PWM). The analog version outputs a voltage that is proportional to the absolute shaft position. PWM output is available in 10-bit (1024 positions) and 12-bit (4096 positions) resolutions and outputs a variable pulse width proportional to the shaft position. Absolute encoders have traditionally been larger, more expensive, and more complex than incremental encoders. In contrast, the small size, low cost ($29.00 / 1 piece price, $21.00 / 100 piece price), and simplicity of the MA3 now provides absolute position feedback for a new spectrum of applications that would otherwise be impractical. Typical applications for the MA3 include front panel control, camera pan-tilt position sensor, rotary valve position sensor, rotary air duct valve position sensor and studio lighting position feedback.• Moment of Inertia 4.1 x 10^-6 oz-in-s² 4.1 x 10^-6 oz-in-s² • Angular Accuracy <0.5 deg. @ 25C <0.5 deg. @ 25C • Angular Accuracy Over Temperature <0.9 deg. @ -40 to 125C <0.9 deg. @ -40 to 125C • Shaft Speed 100 RPM max. continuous 15,000 RPM max. continuous • Acceleration 10,000 rad/sec² 250,000 rad/sec² • Vibration 20G. 5Hz to 2kHz 20G. 5Hz to 2kHz • Shaft Torque 0.5 ± 0.2 in. oz. (D - torque option) • 0.3 in. oz. max. (N - torque option) 0.05 in. oz. max. • Shaft Loading 2 lbs. max. dynamic* • 20 lbs. max. static 1 lb. max. • Bearing Life - (40/P)³ = life in millions of revs. • where P = radial load in pounds • Weight 0.46 oz. 0.37 oz. • Shaft Runout 0.0015 T.I.R. max. 0.0015 T.I.R. max.