Portable devices

Analog Devices has extended its portfolio of general-purpose operational amplifiers with the ADA4841 family of single and dual devices.


Offering low noise and distortion and drawing just 1.1 mA of supply current, the new op amps are suited for power-sensitive applications such as portable instrumentation, high-channel-count measurement and medical applications.


The new op amps meet this requirement by achieving 2-nV/rt-Hz wideband voltage noise and 1.4-pA/rt-Hz wideband current noise. To maintain a low noise environment at lower frequencies these amplifiers have low 1/f noise of 6-nV/rt-Hz and 13-pA/rt-Hz at 10Hz.


Additionally, the amplifiers have low distortion, with 111-dBc spurious free dynamic range (SFDR) at 100 kHz. This level of noise and distortion is accomplished for 1.1 mA of supply current, which saves power and minimizes heat in any application.


The ADA4841-x family has rail-to-rail outputs that allow a signal swing within 100 mV of either supply rail, maximizing the linear range for power supplies from 2.7 V to 12 V. On the input, the common mode voltage range extends down to the negative supply. In addition, these amplifiers offer excellent dc precision with 500 microvolts max offset voltage.


The ADA4841-x family works with leading 16- to 18-bit ADCs, including the AD7685 and AD7686.

The ADA4841-1 is available now in 6-pin SOT-23 (small-outline transistor) and 8-pin SOIC (small-outline integrated circuit) packages, and is priced at $1.59 per unit in 1,000-piece quantities.


The ADA4841-2 is sampling now with production quantities available in September 2005. It is offered in 8-pin SOIC and 8-pin MSOP (micro small-outline package) and is priced at $2.29 per unit in 1,000-piece quantities.

Both devices are offered over the extended industrial temperature range (–40 degrees C to +125 degrees C).