With this capability, the SX8722 can directly connect to a wide array of sensors ranging from 5V chemical to 2 mV 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 0.5 PSI sensitivity needed for a breath analyzer application – saving cost and board space.
“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 for Semtech’s Wireless and Sensing Products Business Unit. “But 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.
It 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. The device 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.