Sensors Expo 2004: integrated, more-connected products
Sensors Expo 2004, in Detroit in June, offered a variety of sensor and communications technologies for many applications.
Sensors Expo 2004, in Detroit in June, offered a variety of sensor and communications technologies for many applications. Advances include new analog-to-digital converters from Analog Devices; a gyro from BEI; wireless innovations from DPAC, Ember, MicroStrain, and ZMD America; a position sensor from Freescale; a combination pressure/temperature sensor from Honeywell; a Fluid Components International ultra low-flow gas mass flowmeter; Microbridge Technologies’ electronically readjustable resistor; and an Optrand Inc. pressure sensor.
Analog Devices Inc . introduced a new family of sigma-delta analog-to-digital converters (ADCs) said to deliver unprecedented low-noise (40 nVrms) and low-power (400 mA) for applications including industrial and instrumentation markets. The AD779x family of devices is sampling now and will be available in production quantities in November 2004. The AD7792 (16-bit), AD7793 (24-bit), AD7798 (16-bit) and AD7799 (24 bit) are available in 16-lead TSSOP (thin shrink small outline package), with prices ranging from $3.80 to $5.10 per unit in 1,000 piece quantities. AD7794 (24-bit) is available in 24-lead TSSOP, and priced at $5.80 per unit in 1,000 piece quantities.
BEI Technologies Inc., Systron Donner Inertial Division , displayed a LCG50 low-cost gyro for robotics, guidance, and control, among other applications, especially where mounting versatility is required and a low unit price is needed. It’s dc in and dc out.
DPAC showed AirborneDirect Ethernet 802.11b Wireless LAN-to-Ethernet and LAN-to-Serial Bridge products. Each about the size of a computer mouse, the products establish a wireless connection between a device and a network and are said to be ideal for retrofit applications. Ember offers wireless semiconductor systems that will support a wide range of mesh networking applications. Those interested can jump in at three levels: an evaluation kit, a developer’s kit, and a chip with code. The multi-hop mesh wireless control network offers more value as more is connected, says Robert Poor, Ember’s chief technology officer. Fluid Components International (FCI) showed an ultra low-flow gas mass flowmeter (insertion type) that can go into a pipe as small as 1/4-in. Customer can supply the T fitting, creating additional savings.
Freescale Semiconductor family of low-g dual-axis sensors measures small forces resulting from tilt, motion, positioning, shock, or vibration.
Freescale Semiconductor (a subsidiary of Motorola Inc.) introduced one family of low-g devices to deliver five sensing functions. MMA62_ _Q microelectromechanical-system (MEMS)-based dual-axis sensors measure small forces resulting from tilt, motion, positioning, shock, or vibration. MMA62_ _Q low-gravity (low-g) sensors range from 1.5 g to 10 g and detect movement in two directions (X and Y axes), eliminating need for two sensors. They’re housed in a 6 x 6 x 1.98 mm, Quad Flat No-Lead (QFN) package, 73% smaller in footprint than the SOIC-20 (small outline integrated package). The sensors range from 50-900 Hz, and low current supply and power consumption help extend battery life and enable quick power-up.
Honeywell combines temperature and pressure sensing in the FS300-100 Combi Sensor.
Honeywell Sensing and Control ’s FS300-100 Combi Sensor is a liquid pressure/temperature device that uses piezoresistive and thermistor sensing technology to measure water pressure and temperature. Dual functions save in material and assembly costs, reducing weight. It can be a separate device or be integrated into other Honeywell control products. Pressure range is 0-3 bar relative, with overpressure of 6 bar and burst pressure of 10 bar. Response time is less than 10 ms for pressure and under 6 seconds for temperature. It has a 5 V dc power supply and voltage output of 0.5-4.5 V dc. Operating temperature is 5-110 °C. Merit Sensor Systems expects growth related to its upcoming move from Santa Clara, CA, to a new 48,000 square foot facility in South Jordan, UT (home of it’s parent company Merit Medical Systems). Merit partners to design, fabricate, assemble and package "mission-critical, cost effective pressure sensors." Microbridge Technologies says its "Rejustor" (electronically readjustable resistor) is completely new technology. It’s an electrically trimmable passive resistor, eliminating the need for laser trimming and trimpots. Rejustor can be trimmed an unlimited number of times without changing performance, maintains the trimmed value without applied power, and allows trimming in the field. TCR (temperature coefficient resistance) may be adjusted, within a certain range, independently of resistor value, giving the analog designer a new tool in temperature compensation of circuits, devices, and sensors. Pricing is expected at $0.40 each, in quantities of a million. There’s an evaluation kit for $2,500. Microbridge won the "Best of Sensors Expo" award for new technology for Rejustor, showing that it’s "destined for widespread application in the analog and mixed-signal world," says Nick Tasker, vice president business development for Microbridge. MicroStrain introduced the Agile-Link product family, a wireless sensor data acquisition system capable of simultaneous, high-speed data acquisition, for use with wireless strain gauges, accelerometers, and temperature and millivolt-level inputs. It uses the license-free ISM band (902-928 MHz.) Separately, the company also says it offers the world's smallest linear displacement sensor, a differential variable reluctance transducer, for critical linear displacement measurements.
Think your pressure sensor has it tough? Optrand Inc . is integrating a pressure sensor with an automotive diesel engine glow plug to improve fuel economy and decrease emissions. The long-life (up to 1 billion cycles or 3 years), low-cost sensors are offered in various packages as small as 1.7 mm dia. and pressure ranges from 0-100 psi (7 bar) to 0-30,000 psi (2,000 bar). These sensors are designed for continuous operation in harsh conditions of high temperature up to 300 °C (such as combustion), high electro-magnetic and radio frequency interference fields (EMI/RFI), and chemically volatile environments. It’s now available in an adapter; a version integrated in the glow plugs is expected in 2007.
ZMD America has been testing ZMD44101, an ultra-low power 900 MHz Transceiver for ZigBee applications, claiming double or more the battery life of competitors for transceivers serving the IEEE 802.15.4 standard (2.4 GHz, 868 MHz, and 915 MHz). The transceiver received Silver Recognition for Best of Show at Sensors Expo 2004. William C. Craig, program manager wireless communications, ZMD Wireless said, "Based on the success to date, ZMD anticipates availability of ZMD44101 development kits in August and production quantities by late Q4/2004."
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—Mark T. Hoske, editor-in-chief, Control Engineering, MHoske@cfemedia.com