POWER AND LINEAR IC SOLUTIONS

Precision 16V Op Amps Offer Best in Class Performance

Two new precision operational amplifiers (op amps) from Analog Devices deliver a combination of industry-best accuracy, power efficiency and versatility with a wide 5V to 16V operating range. The AD8663 and the AD8638 are aimed at industrial, medical and consumer applications.



These op amps are 70% smaller than competing devices, making them particularly suitable for high-density and portable applications where board space is at a premium.

The AD8663 is a precision, low noise, rail-to-rail op amp that addresses the performance, power and cost requirements of portable and battery-operated equipment such as patient monitors, defibrillators, remote industrial controls and optical sensors. These types of higher-voltage portable devices are increasingly adopting lithium-ion, lithium-polymer and other batteries operating at 3V to 16V ranges. This trend has created a demand for signal conditioning components that can support high voltages while also providing excellent power efficiency, thermal management and precision.

The AD8663 meets these requirements by incorporating Analog Devices’ patented DigiTrim in-circuit trimming technology to achieve low offset voltage, 90dB CMRR (Common Mode Rejection Ratio), and 105dB PSRR (Power Supply Rejection Ratio), thus providing 90% better accuracy than other devices in its class. It also features superior performance over varying power supplies and temperatures, with a maximum voltage offset drift of 450µV at +125°C over a wide input range.

The device consumes only 180µA while keeping low-frequency voltage noise at 21nV/√Hz. It is available in an eight-lead LFCSP (3mm x 3mm, Lead-Frame Chip-Scale Package) or an eight-pin SOIC (Small-Outline Integrated Circuit) package. A dual-channel version, the AD8667, is available in an eight-pin MSOP (Mini Small-Outline Package) or an 8-pin SOIC.

The AD8638 is a zero-drift precision device that can accommodate wide variations in temperature, power supply, load and input signal without introducing signal conditioning errors. It extends the operating voltage and temperature range for both single- and dual-supply applications by using Analog Devices’ iCMOS process and patented auto-zero and low-drift technologies. Delivering 140dB CMRR and 140dB PSRR, it is up to 10dB more accurate than competing products.

The converter features a 10µV offset voltage over temperature and a maximum offset drift of 80nV/°C, reducing the need for additional circuitry such as temperature correction loops. Offering four times faster output saturation recovery time than other op amps in its class, the AD8638 is available in a Small Outline Transistor SOT-23 package.

Features: AD8663

• Low offset voltage: 175μV maximum
• Low supply current: 275μA maximum per amplifier
• Single-supply operation: 5V to 16V
• Low noise: 23nV/√Hz
• Low input bias current: 300fA
• Unity-gain stable
• 3mm x 3mm, eight-lead LFCSP or eight-lead MSOP

Features: AD8638

• Low offset voltage: 9μV maximum
• Low offset drift: 0.04μV/°C
• Rail-to-rail output swing
• +16V single- or ±8V dual-supply operation
• High gain and CMRR: 133dB typical
• High PSRR: 143dB typical
• Very low input bias current: 40pA
• Low supply current: 1.3mA
• SOIC or SOT-23 packages

Applications

• Patient monitors
• Defibrillators
• Remote industrial controls
• Optical sensors
• High-voltage portable devices
• Pressure, temperature and fibre-optic sensors
• Thermocouples, strain gauges and position sensors
• Portable industrial tools
• Industrial instrumentation
• Automotive applications
• Sensing in harsh environments
• Precision conversion in fluctuating environmental conditions

For further information, including Datasheets for the AD8638 or AD8663/7/9, please click here