
Analog Devices
PRODUCT DESCRIPTION
The AD706 is a dual, low power, bipolar op amp that has the low input bias current of a BiFET amplifier, but which offers a significantly lower IB drift over temperature. It utilizes superbeta bipolar input transistors to achieve picoampere input bias current levels (similar to FET input amplifiers at room tempera ture), while its IB typically only increases by 5× at 125°C (unlike a BiFET amp, for which IB doubles every 10°C for a 1000× increase at 125°C). The AD706 also achieves the microvolt offset voltage and low noise characteristics of a precision bipolar input amplifier.
Since it has only 1/20 the input bias current of an OP07, the AD706 does not require the commonly used “balancing” resis tor. Furthermore, the current noise is 1/5 that of the OP07, which makes this amplifier usable with much higher source impedances. At 1/6 the supply current (per amplifier) of the OP07, the AD706 is better suited for today’s higher density boards.
The AD706 is an excellent choice for use in low frequency active filters in 12- and 14-bit data acquisition systems, in precision instrumentation and as a high quality integrator. The AD706 is internally compensated for unity gain and is available in five performance grades. The AD706J and AD706K are rated over the commercial temperature range of 0°C to +70°C. The AD706A and AD706B are rated over the industrial temperature range of –40°C to +85°C.
The AD706 is offered in three varieties of an 8-lead package: plastic mini-DIP, hermetic cerdip and surface mount (SOIC). “J” grade chips are also available.
FEATURE
HIGH DC PRECISION
50 μV max Offset Voltage
0.6 μV/8C max Offset Drift
110 pA max Input Bias Current
LOW NOISE
0.5 μV p-p Voltage Noise, 0.1 Hz to 10 Hz
LOW POWER
750 μSupply Current
Available in 8-Lead Plastic Mini-DlP, Hermetic Cerdip
and Surface Mount (SOIC) Packages
Available in Tape and Reel in Accordance with
EIA-481A Standard
Single Version: AD705, Quad Version: AD704
PRIMARY APPLICATIONS
Low Frequency Active Filters
Precision Instrumentation
Precision Integrators