PCB-ENDEVCO ACCELEROMETERS
PCB Accelerometers
High Temperature ICP Accelerometers (≤ +180 ºC /+356 ºF)
These sensors combine proven quartz and ceramic shear sensing technology with specialized, built-in microelectronic signal conditioning circuitry to achieve dependable operation in extreme temperatures and through repetitive temperature cycling. Laser-welded, hermetically sealed, lightweight titanium or stainless steel housings offer further protection from the environment. Prior to shipment, each sensor undergoes a battery of tests to ensure survivability for its intended use. Such tests include temperature soak at elevated temperatures, temperature cycling, and exposure to highly accelerated screening procedures with hydraulically actuated shakers.
High Temp Accelerometers ≥ +254 to +649° C (+490 to +1200° F)
Charge mode output accelerometers from PCB use piezo-ceramic sensing elements that output an electrostatic charge signal proportional to the applied acceleration. These sensors can operate at extremely high temperatures because they do not contain the built-in signal conditioning electronics that limit the temperature range of ICP accelerometers. Charge mode sensors are used in the testing of gas and steam turbines, jet engines, high power motors, exhaust systems and automobile engines where temperatures can range from 260° C (500° F) to 649° C (1200° F). External signal conditioning is required to interface charge mode measurement signals to readout or recording instruments. The charge output signals can be conditioned with either a laboratory style charge amplifier or an in-line fixed charge converter. Each of these products convert the charge output to a low impedance voltage signal. It is important to note that measurement resolution and low-frequency response for charge mode sensing systems are dependent upon the noise floor and discharge time constant characteristics of the signal conditioning and readout devices used.
Cryogenic ICP Accelerometers
Cryogenic ICP accelerometers are specifically designed to operate at temperatures below the typical -54 ºC (-65 ºF) temperature limit of most voltage mode sensors. The use of specialized, built-in, cryogenic circuitry and quartz shear sensing technology promote survivability in demanding environments such as liquid nitrogen. Each sensor is hermetically sealed and individually tested to determine the thermal coefficient of sensitivity at -196 ºC (-320 ºF) ensuring reliable operation and accurate measurements. These sensors have been successfully used in the presence of liquid helium during structural testing of rocket boosters.
Damped MEMS High-G Shock Accelerometers
Damped MEMS high-amplitude shock accelerometers represent state-of-the-art industry technology for miniature, high amplitude, DC response acceleration sensors. This series is capable of measuring long duration transient motion, as well as responding to and surviving extremely fast rise times, typical of a high-g shock event as found in explosive, gun and impact testing. Both packaged and OEM configurations are offered, to fulfill a variety of installation requirements. The hermetically sealed sensing element is air-damped with over range stops intended to improve survivability and is a full active Wheatstone bridge with high input resistance for low power consumption. It is micromachined from single crystal silicon and manufactured with the latest advances in etching techniques and equipment using deep reactive ion etching (DRIE).
ENDEVCO Accelerometers
SMT Surface Mount MEMS High-G Shock Accelerometers
Piezoresistive MEMS high-amplitude shock accelerometers represent state-of-the-art industry technology for miniature, high amplitude, DC response acceleration sensors. This series is capable of measuring long duration transient motion as well as responding to and surviving extremely fast rise times, typical of a high-g shock event as found in explosive, gun and impact testing. Both packaged and OEM configurations are offered, to fulfill a variety of installation requirements. The hermetically sealed sensing element is air-damped with over range stops intended to improve survivability and is a full active Wheatstone bridge with high input resistance for low power consumption. It is micromachined from single crystal silicon and manufactured with the latest advances in etching techniques and equipment using deep reactive ion etching (DRIE).
Piezoelectric (PE) accelerometers
All mechanical accelerometer designs are based on a simple spring-mass principle in which strain is generated in relation to amplitude and frequency of the dynamic motion. In a PiezoElectric (PE) accelerometer, this strain is applied directly to the PE element, which develops an electrical charge proportional to mechanical motion. Different material and configurations of PE accelerometer elements are used to support specific applications.
Piezoresistive (PR) accelerometers
Strain gauge accelerometer designs based on a Wheatstone bridge arrangement consist of a rugged monolithic assembly with solid-state MEMS resistors that change in resistance in proportion to applied mechanical strain.
Integrated electronics piezoelectric (IEPE) accelerometers
All mechanical accelerometer designs are based on a simple spring-mass principle in which strain is generated in relation to amplitude and frequency of the dynamic motion. In a PiezoElectric (PE) accelerometer, this strain is applied directly to the PE element, which develops an electrical charge proportional to mechanical motion. Different material and configurations of PE accelerometer elements are used to support specific applications.
Variable capacitance (VC) accelerometers
Feature a silicon MEMS capacitive sensing element that is anodically bonded to a lid and base to form a parallel plate, differential capacitor pair. The accelerometers feature DC response, gas damping for good frequency coverage and rugged construction. Integral electronics with DC excitation provide a high-level, low-impedance output signal that is stable.