Variable Capacitance Accelerometers with Piezoresistive Electrical Interface

Aug. 13, 2010
Dytran Instruments is pleased to introduce a new technology of high performance,variable capacitance (VC) accelerometers. The 7600B series is a family of DC response accelerometers which were designed to directly replace piezoresistive units in new or existing applications.The 7600B series accelerometers utilize a capacitive sensing element and an advanced ASIC to simulate the operation of a piezoresistive bridge. It combines an integrated VC accelerometer chip with high drive, low impedance buffering for measuring acceleration in aerospace, automotive, commercial and industrial environments.These accelerometers are tailored for zero to medium frequency instrumentation applications. The module contains a hermetically sealed micro-machined capacitive sensing element, a custom integrated circuit amplifier, and differential output stages. It’s hermetically sealed titanium case has a M4.5 X 0.35 4-pin receptacle, and is easily mounted via two 4-40 screws.On-board regulation is provided to minimize the effects of supply voltage variation. It is relatively insensitive to temperature changes and thermal gradients. The cable shield is electrically connected to the titanium case, and the power and signal wires are isolated from the case.The unique benefit of the 7600B series is that while they utilize variable capacitance technology, they are powered with the same power supply as piezoresistive and strain gage sensors. These units can also operate as standalone VC accelerometers with differential output or be used in place of Piezoresistive, bridge type accelerometers.The 7600B series of accelerometers responds to both DC and AC acceleration. Typical applications in which they can be used include crash testing, air bag testing, ride quality, flight testing and seismic monitoring.