Digital pulse density output MEMS variable capacitance accelerometers

August 20, 2014 // By Graham Prophet
Model 1410 from Silicon Designs is a family of digital pulse density output MEMS variable capacitive (VC) accelerometers, designed to reliably measure both vibration and acceleration, with very low power consumption and high long-term bias stability (1000 ppm typical). Consuming 2 mA with 5V excitation makes them suitable for use within low current applications.

The Model 1410 uses a clock frequency between 100 kHz and 1.0 MHz and produces a pulse density output relative to acceleration. Units are available in seven standard ranges, from ±2g to ±200g, with sensitivities from 0.625 kHz/g (200g range) to 62.5 kHz/g (2g range). Frequency response is from 0 to 400 Hz (±2 g) up to 0 to 2000 Hz (±200 g) at fixed intervals according to selected g range, successfully responding to DC (continuous) and dynamic acceleration. A robust MEMS VC accelerometer design allows the Model 1410 to withstand mechanical shock inputs up to 5000 g (2000 g on low range units – 2g and 5g FSO) without damaging the unit. All units are serialised for traceability and quality control. Custom ranges are available upon request.

Design of the Model 1410 incorporates Silicon Designs' own proprietary MEMS sensing element, which features constant nitrogen damping over its full operating temperature range (-55 to +125°C). Each unit is hermetically sealed in a miniature package measuring 0.360 x 0.350 x 0.165 in. terminating in either a 20-pin LCC or JLCC type connector. This suits them to placement on circuit boards, in small packages or for OEM applications. The digital output signal of the Model 1410 is compatible with TTL/CMOS devices, to interface to microprocessors and other instrumentation. The SDI Model 1410 may also be used as a higher performance drop-in replacement for the Model 1010.

Typical applications include microcomputer controlled applications, such as automotive airbags, active suspension, adaptive brakes, and security systems; fusing; shipping recorders; appliances; vibration measurement and analysis, and machinery control.

Silicon Designs;