Title :
An IC for closed-loop micromotor control
Author :
Rao, N.K. ; Hartsfield, D.K. ; Purushotham, A. ; Garverick, S.L.
Author_Institution :
Dept. of Electr. Eng. & Appl. Phys., Case Western Reserve Univ., Cleveland, OH, USA
Abstract :
A micromotor control integrated circuit (MCIC) which enables closed-loop control of an electrostatic micromotor is described. The MCIC consists of low-noise sense electronics designed to detect critical rotor angles to a resolution of 0.5°(0.05 fF) at a 1 MHz sampling rate, and control logic which cycles the micromotor drive state during continuous rotation to maintain maximum torque, independent of the loading. The MCIC was fabricated using a 2-μm, n-well CMOS process and all circuits, analog and digital, function as expected. Preliminary measurements indicate that the input-referred noise of the sense amplifier is very close to the design objective of 32 μV RMS
Keywords :
CMOS integrated circuits; closed loop systems; electrostatic devices; micromotors; 1 MHz; 2 micron; 2-μm n-well CMOS process; 32 muV; closed-loop micromotor control; control logic; electrostatic micromotor; input-referred noise; low-noise sense electronics; maximum torque; measurements; micromotor control integrated circuit; micromotor drive state; rotor angles detection; sampling rate; sense amplifier; Capacitance; Electrostatics; Microactuators; Micromotors; Rotors; Sampling methods; Silicon; Stators; Switches; Torque control;
Conference_Titel :
Signals, Systems, and Electronics, 1995. ISSSE '95, Proceedings., 1995 URSI International Symposium on
Conference_Location :
San Francisco
Print_ISBN :
0-7803-2516-8
DOI :
10.1109/ISSSE.1995.498057
