Silicon Designs has launched a family of digital pulse density output MEMS variable capacitive (VC) accelerometers designed to reliably measure both vibration and acceleration, writes Nick Flaherty.
The Model 1410 has a very low power consumption and high long-term bias stability (1000 PPM typical) that makes it ideal for use within low current applications consuming only 2 mA with 5 volts excitation from a CMOS microcontroller.
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 unique standard ranges, from ±2g to ±200g, with sensitivities from 0.625kHz/g (with a 200g range) to 62.5kHz/g (or a 2g range).
Frequency response is from 0 to 400Hz (±2g) up to 0 to 2000Hz (±200g) 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 5000g (2000g 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.
The design of the Model 1410 uses 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”L X 0.350-in X 0.165-in, terminating in either a 20-pin LCC or JLCC type connector. This makes them ideal for 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, allowing for easy interface to microprocessors and other instrumentation. The SDI Model 1410 may also be used as a higher performance drop-in replacement for the popular Model 1010.
Typical applications for the Model 1410 include microcomputer controlled applications such as automotive airbags, active suspension, adaptive brakes, and security systems; fuzing; shipping recorders; appliances; vibration measurement and analysis, and machinery control. Standard g ranges are available in low-to-medium sized quantities for immediate customer shipment. Larger quantities are available with four-week lead times.