Analog Devices Breaks New Ground for Vital Sign Detection and Portability in Patient Monitoring Medical Equipment.

NORWOOD, Mass. -- ADI's new JFET-input in-amp improves performance and shrinks package size by 50%, increasing channel densities in patient monitors and portable medical electronics.

Analog Devices Inc. (NYSE: ADI), a global leader in high-performance semiconductors for signal processing applications and market leader in amplifier ICs, today continues its long history of serving the medical electronics industry by introducing the AD8220 JFET-input instrumentation amplifier. The AD8220 enhances the detection of patient vital signs in both fixed-line and transportable electrocardiograms (ECGs), electroencephalograms (EEGs) and other types of patient monitoring devices. Housed in an 8-lead plastic MSOP (mini-small-outline package) that is half the size of competing devices, the AD8220 in-amp allows designers of medical equipment to break new ground by freeing up additional board space to significantly increase ECG and EEG channel density, allowing for smaller medical monitoring systems. Monitoring equipment with high channel density also gives medical professionals more measurement points for very small signals like heart pulses and brain activity while protecting patient vital signs from electrical interference. In addition, the AD8220 operates on a single low-voltage power supply that draws only 700 micron A, making it ideally suited for use in portable patient monitoring systems.

The AD8220 features an extremely low input bias current of just 4 pA (pico amps), which is less than half the level of competing components and addresses a significant source of signal error in precision instruments. The AD8220 also achieves an 80 dB common mode rejection ratio (CMRR) up to 10 kHz (G=1), while competing in-amps guarantee only 72 dB to 200 Hz. With significantly lower input bias current and higher CMRR, health care professionals can now measure heart pulses, electrical brain waves, and other patient vital signs at previously undetectable levels. The high CMRR, meanwhile, shields these signals from outside interference by rejecting electrical noise from other parts of the human body.

"For monitoring devices that measure very small electrical currents, the small package of the AD8220 enables designers to increase system channel density, which means we can fit more of these critical signal conditioning functions into a given space," said Lew Counts, vice president, Advanced Linear Products at Analog Devices. "At the same time, we guarantee to reject high frequency noise at levels competing solutions can not. The significance is engineers designing patient monitoring equipment with ADI's AD8220 in-amp improve overall system dynamic range and performance, without compromising on power or cost."

About the AD8220

With JFET (junction field effect transistor) inputs, the AD8220 in-amp achieves a guaranteed input bias current of 20 pA, maximum, and 4 pA, typical. It specifies a 1-nA input bias current over temperature, and 2 micron V/degrees C input offset voltage temperature drift. The rail-to-rail output of the AD8220 allows designers to improve dynamic range by increasing the gain further before reaching the supply rails. Furthermore, the AD8220's 80 dB CMRR (G=1) over frequency ensures that only the desired signals are monitored and unwanted common-mode signals are rejected.

Applications

The AD8220 is ideally suited for patient monitoring systems, where its small size, low current noise and low input bias current increase the sensitivity and noise rejection of fixed-line and portable medical equipment, such as ECG and EEG systems. The low input bias and high CMRR characteristics also make the AD8220 a fit for industrial automotation applications, such as electrometers and other precision instrumentation systems where extremely small currents must be measured in electrically noisy environments.

Pricing and Availability

The AD8220 is currently sampling and available in an 8-lead MSOP. The AD8220 is priced at $2.29 per unit, in 1,000-piece quantities. For more information, please visit: http://www.analog.com/AD8220.

About Analog Devices

Innovation, performance, and excellence are the cultural pillars on which Analog Devices has built one of the longest standing, highest growth companies within the technology sector. Acknowledged industry-wide as the world leader in data conversion and signal conditioning technology, Analog Devices serves over 60,000 customers, representing virtually all types of electronic equipment. Celebrating 40 years as a leading global manufacturer of high-performance integrated circuits used in analog and digital signal processing applications, Analog Devices is headquartered in Norwood, Massachusetts, with design and manufacturing facilities throughout the world. Analog Devices' common stock is listed on the New York Stock Exchange under the ticker "ADI" and is included in the S&P 500 Index.