Datasheet AD704 (Analog Devices)

Picoampere Input Current Quad Bipolar Op Amp AD704 FEATURES CONNECTION DIAGRAMS High dc precision OUTPUT 1 16 OUTPUT 150 µV maximum offset voltage –IN 2 1 4 15 –IN 1.5 µV/°C maximum offset voltage drift OUTPUT 1 14 OUTPUT +IN 3 14 +IN 270 pA maximum input bias current AD704 –IN 2 1 4 13 –IN +VS 4 13 –VS TOP VIEW 0.3 pA/°C typical I +IN 3 12 +IN +IN 5 12 +IN B drift AD704 Low noise: 0.5 µV p-p +VS 4 11 –VS –IN 6 2 3 11 –IN TOP VIEW +IN 5 10 +IN Typical noise: 0.1 Hz to 10 Hz OUTPUT 7 10 OUTPUT –IN 6 2 3 9 –IN NC 8 9 NC Low power: 600 µA maximum supply current per amplifier (Not to Scale)
002
OUTPUT
001
7 8 OUTPUT (Not to Scale) Dual version: AD706 NC = NO CONNECT
00818- 00818- Figure 1. 14-Lead Plastic DIP (N) Figure 2. 16-Lead SOIC (R) Package
APPLICATIONS T1 T4 Industrial/process controls N1 N4 –I OU NC OU –I Weigh scales 3 2 1 20 19 ECG/EKG instrumentation +IN1 4 18 +IN4 1 4 Low frequency active filters NC 5 17 NC AD704 GENERAL DESCRIPTION +V 6 TOP VIEW S 16 –VS (Not to Scale) NC 7 15 NC
The AD704 is a quad, low power bipolar op amp that has the
2 3 +IN2 8 14 +IN3
low input bias current of a BiFET amplifier and offers a signifi- cantly lower IB drift over temperature. It uses superbeta bipolar
9 10 11 12 13 NC = NO CONNECT
input transistors to achieve picoampere input bias current levels 003
N2 T2 T3 NC N3 –I –I
(similar to FET input amplifiers at room temperature), while its
OU OU
00818- Figure 3. 20-Terminal LCC IB typically increases only by 5× at 125°C (unlike a BiFET amp, (E-20-1) Package for which IB doubles every 10°C, resulting in a 1000× increase at
100
125°C). In addition, the AD704 achieves 150 μV offset voltage and the low noise characteristics of a precision bipolar input op amp. Because it has only 1/20 the input bias current of an OP07, the
10
AD704 does not require the commonly used balancing resistor.
A) TYPICAL JFET AMP n
Furthermore, the current noise is 1/5 that of the OP07, which
( B
makes the AD704 usable with much higher source impedances.
L I 1 A IC
At 1/6 the supply current (per amplifier) of the OP07, the
P TY
AD704 is better suited for today’s higher density circuit boards
0.1
and battery-powered applications.
AD704
The AD704 is an excellent choice for use in low frequency active filters in 12- and 14-bit data acquisition systems, in precision
0.01 –55 25 125
004 instrumentation, and as a high quality integrator. The AD704 is
TEMPERATURE (°C)
00818- internally compensated for unity gain stability. The AD704J is Figure 4. Input Bias Current Over Temperature rated over the commercial temperature range of 0°C to 70°C.
Table 1. Low I
The AD704A is rated over the industrial temperature of −40°C
B @ 125°C
to +85°C. The AD704S is rated over the military temperature
Model 30V 16V 1.3 to 5V Next Generation
range of −55°C to +125°C, processed to MIL-STD-883B. Single N/A AD8663 AD8603 N/A Dual AD706 AD8667 AD8607 AD8622 Quad AD704 AD8669 AD8609 AD8624
Rev.
E
Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 781.329.4700 www.analog.com Trademarks and registered trademarks are the property of their respective owners. Fax: 781.461.3113 ©
2001-2010
Analog Devices, Inc. All rights reserved.
Document Outline Features Applications General Description Connection Diagrams Revision History Specifications Absolute Maximum Ratings ESD Caution Typical Performance Characteristics Theory of Operation Outline Dimensions Ordering Guide