Dec 13 2006 -- A complete high-resolution data acquisition device for micro-electromechanical systems (MEMS) sensors used in portable industrial and consumer sensing applications has been unveiled by Semtech. The SX8722 is part of the company's ZoomingADC sensing machine product family.
The SX8722 interfaces with most Wheatstone bridge chemical, pressure or magnetic sensors to condition and read data. The device features ZoomingADC, a 16-bit analog / digital converter (ADC) with a 10-bit preamplifier to allow the device to 'zoom in' on a small portion of the analog signal and apply the full 16-bit ADC to that part of the signal.
With this capability, the SX8722 can directly connect to a wide array of sensors ranging from 5V chemical to 2mV magnetic sensors without the need for an external amplifier. A built-in input multiplexer means the SX8722 can measure up to four differential sensors, seven single-ended sensors or a combination thereof. The 1000-times gain of the preamplifier also gives designers the freedom to achieve a given level of sensitivity using a less sensitive, and usually lower cost, sensor. For example the ZoomingADC can enhance the signal from a 5 pounds per square inch (PSI) breath sensor to deliver the 0.5PSI sensitivity needed for a breath analyzer application - saving cost and board space, says the company.
"We've developed the SX8722 as a standard product with the features and software necessary for it to be dropped into an application and work without additional development," said Michel Chevroulet, Sensing Product Group manager, Semtech Wireless and Sensing Products Business Unit. "The ZoomingADC feature gives our customers the best of both worlds because they also get a level of programmability that makes the device equally suited to the cost-sensitive standalone product as well as the broad-based sensor product lines that need to accommodate thousands of different sensors for niche applications."
The low-power SX8722 is optimized for battery applications with two power-saving shutdown modes and a power supply range of 2.4V to 5.5V. The SX8722's 7mm x 7mm leadless package is well suited for portable consumer (compass or altimeter) or industrial applications.
The device is a complete data acquisition solution that includes embedded software for basic data acquisition functions for fast development of sensor solutions. For more advanced functionality, the SX8722 features a 2-wire I2C serial bus for connection to a general-purpose microcontroller. It also features programmable high and low threshold alarm outputs enabling it to work without an MCU in standalone sensor devices and be able to trigger an LED to indicate an alarm condition. The company offers comprehensive design assistance, including field- and factory-based support.
