Microelectromechanical accelerometer with resonance-cancelling control circuit including an idle state

Patent · 31 December 2000

OSTI ID:874050

Chu, Dahlon D ^[1]; Campbell, David V ^[1]

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1. Albuquerque, NM

A digital feedback control circuit is disclosed for use in an accelerometer (e.g. a microelectromechanical accelerometer). The digital feedback control circuit, which periodically re-centers a proof mass in response to a sensed acceleration, is based on a sigma-delta (.SIGMA..DELTA.) configuration that includes a notch filter (e.g. a digital switched-capacitor filter) for rejecting signals due to mechanical resonances of the proof mass and further includes a comparator (e.g. a three-level comparator). The comparator generates one of three possible feedback states, with two of the feedback states acting to re-center the proof mass when that is needed, and with a third feedback state being an "idle" state which does not act to move the proof mass when no re-centering is needed. Additionally, the digital feedback control system includes an auto-zero trim capability for calibration of the accelerometer for accurate sensing of acceleration. The digital feedback control circuit can be fabricated using complementary metal-oxide semiconductor (CMOS) technology, bi-CMOS technology or bipolar technology and used in single- and dual-proof-mass accelerometers.

• Research Organization: SANDIA CORP
• DOE Contract Number: AC04-94AL85000
• Assignee: Sandia Corporation (Albuquerque, NM)
• Patent Number(s): US 6301965
• OSTI ID: 874050
• Country of Publication: United States
• Language: English

Related Subjects

/73/
acceleration
accelerometer
accelerometers
accurate
acting
additionally
auto-zero
based
bi-cmos
bipolar
calibration
capability
circuit
circuit including
cmos
comparator
complementary
configuration
control
control circuit
digital
disclosed
dual-proof-mass
due
fabricated
feedback
feedback control
filter
generates
idle
including
mass
mechanical
metal-oxide
microelectromechanical
move
notch
periodically
proof
re-center
re-centering
re-centers
rejecting
resonance-cancelling
resonances
response
semiconductor
sensed
sensing
sigma-delta
sigmadelta
signals
single-
switched-capacitor
technology
third
three-level
trim