POWER AND LINEAR IC SOLUTIONS

In-Amps Combine Speed, Precision and Low Power

The AD8250 and AD8251 from Analog Devices are digitally programmable instrumentation amplifiers (in-amps) that offer unmatched accuracy and bandwidth plus the speed and precision needed for advanced industrial and instrumentation applications. They will be particularly useful to designers of test, control and high-speed data acquisition systems needing to implement fast, accurate measurements and robust signal conditioning over large voltage ranges.



The new in-amps offer bandwidth of up to 12MHz while delivering 75% lower drift than comparable devices. Settling time to 0.01% is just 0.5µs, making the AD8250 and AD8251 highly suitable for multi-channel data acquisition systems, automatic test equipment and biomedical instruments. Through the use of Analog’s sub-micron iCMOS (industrial CMOS) process technology, these in-amps also cut current requirements by 75% to just 3.5mA. They are available in space-saving 10-lead MSOP (Mini Small-Outline Plastic) packages, which are 90% smaller than competing devices.

By combining programmability, high bandwidth and DC accuracy, the devices will allow designers for many environments to replace a variety of in-amps or a combination of discrete devices with a single integrated solution. This in turn will allow increased performance, higher channel density and improved ease-of-use. Their 1µV/°C offset drift and 10ppm/°C gain drift are the lowest of any programmable-gain in-amp and they can operate with ±5V to ±12V power supplies.

The gain of the AD8250 and AD8251 is programmable via two gain control bits that can be set permanently, or programmed in-system, in any of three ways: latched using the clock input; set within 1µs in transparent mode or strapped to a high- or low-voltage potential. The AD8250 offers gain settings of unity, two, five and 10 and the AD8251 gain settings of unity, two, four and eight.

The devices are tailored to operate with high-performance ADCs such as Analog’s AD7621, AD7671/74/77/78/79, AD7685 and AD7946 PulSAR components and with the company’s ADR431 and ADR435 voltage references. They are designed for use within the extended -40°C to +85°C temperature range.

Features

• Digitally programmable instrumentation amps
• Four gain settings per device, pin- or digitally-programmable
• Low gain drift: 10 ppm/°C
• Low offset drift: 1µV/°C
• Fast settling time: 0.5µs to 0.01%
• Low power: 3.5mA (typical)
• 10-pin MSOP package
• Wide supply range: ±5V to ±12V
• High CMRR (Common Mode Rejection Ratio)
• High slew rate
• Low noise
• Extended temperature tolerance: -40°C to 85°C

Applications

• Data acquisition
• Biomedical analysis
• Test and measurement
• Industrial control

For further information, including a copy of the Designers Guide To Instrumentation Amplifiers, please click here