National Semi Revolutionizes Sensor System Design

SANTA CLARA, CA /PRNewswire/ -- National Semiconductor Corp. (NYSE: NSM) introduced two configurable sensor analog front-end (AFE) integrated circuits (ICs) with unique technology that work together with new tools to fast-track signal path designs for a variety of sensors from major global manufacturers.

The configurable sensor AFE ICs and WEBENCH Sensor AFE Designer enable the design engineer to select a sensor, design and configure the solution and download configuration data to the sensor AFE. A typical sensing application that today may require several boards and up to 25 components is reduced to just one of National's ICs. Weeks or months to create a sensor system design is reduced to just minutes using National's new products and tools.

Sensor systems today are used in every major industry for critical monitoring and control applications. These systems are shrinking in size, must consume less power and have higher reliability.

"Sensor-based system designs are time-consuming and complicated to develop, requiring an optimal design for each system," said Anita Ganti, Precision Systems Business Unit Director at National. "Until now, designers have developed customized analog solutions that took weeks or even months to develop, but we can now help them get to market more quickly."

The first in a family of products, National's two configurable sensor AFE products are each customized to a specific sensor application and have a variety of features, including programmable current sources, voltage reference options and adjustable sample rates. The LMP91000 is the industry's first fully configurable, low-power potentiostat that provides a complete, integrated signal path solution between a sensor and analog-to-digital converter (ADC). The LMP90100 is the industry's first multi-channel, low power, 24-bit sensor AFE with true continuous background calibration and diagnostics for high performance transmitter and transducer applications.

The WEBENCH Sensor AFE Designer includes technical specifications for hundreds of temperature, pressure and chemical sensors. The database features products from Omega Engineering, Inc., Honeywell Sensing & Control, Tempco Electric Heater Corp. and All Sensors Corp.

About National's LMP90100
National's LMP90100 is the industry's first multi-channel, low power, 24-bit sensor AFE with true continuous background calibration and diagnostics for high performance transmitter and transducer applications. National's patented continuous background calibration effectively eliminates offset and gain error over time and temperature. Offset and gain error are determined without disturbing the measured signal. The LMP90100 features a 24-bit sigma-delta ADC with a flexible input (mux) configuration to interface with any combination of differential or single-ended inputs. Signal gains (1, 2, 4, 8, 16, 32, 64 and 128), sample rate and diagnostics are programmable for each sensor and two matched current drives are available to drive sensors. The LMP90100 draws less than 0.7 mA on average and is guaranteed over the entire –40°C to 125°C temperature range, making it ideal for temperature transmitter or 4–20 mA applications.

About National's LMP91000
National's LMP91000 is the industry's first fully configurable, low-power potentiostat that provides a complete, integrated signal path solution between a sensor and ADC. The programmable AFE is well-suited for use in micro-power chemical and gas sensing applications such as three-electrode single gas and two-terminal oxygen sensors. The LMP91000 measures current in a potentiostat that is proportional to the gas concentration. It generates an output voltage proportional to the cell current using a transimpedance amplifier. Transimpedance gain is user programmable through an I2C compatible interface, allowing the LMP91000 to support toxic gas sensitivities over a range of 0.5 nA/ppm to 9.5 nA/ppm. Ultra-low power makes the LMP91000 optimal for battery-operated systems, as well as 4–20 mA transmitter applications. The cell voltage and cell output gain are user-selectable using on-board programmability. Together, they allow the user to support a wide range of gases and gas concentrations with a total current consumption for the device as low as 10 µA on average. The I2C interface allows the user to verify sensor performance and an embedded temperature sensor provides an additional output to monitor temperature. The LMP91000 operates over a voltage range of 2.7V to 5.5V.

About National's WEBENCH Sensor AFE Designer
National's new WEBENCH Sensor AFE Designer joins National's award-winning portfolio of online WEBENCH tools. A bench-top evaluation tool with a hardware interface is available to minimize engineering design time and facilitate prototype evaluation. This system allows the user to download configuration data from their design to the sensor AFE, attach sensors and start their evaluation. Watch a video demonstration.

Pricing and Availability
Offered in a 28-pin TSSOP package, National's LMP90100 is available now and priced at $4.95 in 1,000-unit quantities. Also available now, the LMP91000 is offered in a 14-pin LLP package and priced at $3.95 in 1,000-unit quantities. AFE products targeting faster and higher performance applications and expanding into other markets like medical will be introduced in the coming year. More information about National's sensor AFE products, WEBENCH Sensor AFE Designer and other support tools is available at the Sensor Analog Front End (AFE) web page.

About National Semiconductor
National Semiconductor is a leader in power management technology. Known for its easy-to-use analog integrated circuits and world-class supply chain, National's high-performance analog products enable its customers' systems to be more energy efficient. Headquartered in Santa Clara, CA, National reported sales of $1.42 billion for fiscal 2010.