Wide Supply Range, Rail-to-Rail Output Instrumentation Amplifier AD8426 FEATURES CONNECTION DIAGRAM 2 channels in a small, 4 mm 4 mm LFCSP LFCSP package has no metal pad 16 15 14 13 More routing room AD8426 No current leakage to pad 12 IN2 IN1 1 Gain set with 1 external resistor RG1 2 11 RG2 Gain range: 1 to 1000 RG1 3 10 RG2 Input voltage goes below ground +IN2 +IN1 4 9 Inputs protected beyond supplies Very wide power supply range 5 678 Single supply: 2.2 V to 36 V Dual supply: 1.35 V to 18 V Bandwidth (G = 1): 1 MHz Figure 1. CMRR (G = 1): 80 dB minimum 1 Input noise: 24 nV/Hz Table 1. Instrumentation Amplifiers by Category Typical supply current (per amplifier): 350 A General- Zero Military Low High Speed Specified temperature range: 40C to +125C Purpose Drift Grade Power PGA AD8220 AD8231 AD620 AD627 AD8250 APPLICATIONS AD8221 AD8290 AD621 AD623 AD8251 Industrial process controls AD8222 AD8293 AD524 AD8235 AD8253 Bridge amplifiers AD8224 AD8553 AD526 AD8236 Medical instrumentation AD8228 AD8556 AD624 AD8426 Portable data acquisition AD8295 AD8557 AD8226 Multichannel systems AD8227 1 See www.analog.com for the latest instrumentation amplifiers. GENERAL DESCRIPTION The AD8426 is a dual-channel, low cost, wide supply range The AD8426 is designed to make PCB routing easy and efficient. The two amplifiers are arranged in a logical way so that typical instrumentation amplifier that requires only one external resistor to set any gain from 1 to 1000. application circuits have short routes and few vias. Unlike most chip scale packages, the AD8426 does not have an exposed metal The AD8426 is designed to work with a variety of signal pad on the bottom of the part, which frees additional space for voltages. A wide input range and rail-to-rail output allow the routing and vias. The AD8426 offers two in-amps in the equivalent signal to make full use of the supply rails. Because the input board space of a typical MSOP package. range can also go below the negative supply, small signals near ground can be amplified without requiring dual supplies. The The AD8426 is ideal for multichannel, space-constrained industrial AD8426 operates on supplies ranging from 1.35 V to 18 V applications. Unlike other low cost, low power instrumentation for dual supplies and 2.2 V to 36 V for a single supply. amplifiers, the AD8426 is designed with a minimum gain of 1 and can easily handle 10 V signals. With its space-saving LFCSP The robust AD8426 inputs are designed to connect to real- package and 125C temperature rating, the AD8426 thrives in world sensors. In addition to its wide operating range, the tightly packed, zero airflow designs. AD8426 can handle voltages beyond the rails. For example, with a 5 V supply, the part is guaranteed to withstand 35 V The AD8226 is the single-channel version of the AD8426. at the input with no damage. Minimum and maximum input bias currents are specified to facilitate open-wire detection. Rev. 0 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. 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Trademarks and registered trademarks are the property of their respective owners. +V +V S S REF1 OUT1 REF2 OUT2 V V S S 09490-001AD8426 TABLE OF CONTENTS Features .............................................................................................. 1 Gain Selection ............................................................................. 21 Applications ....................................................................................... 1 Reference Terminal .................................................................... 22 Connection Diagram ....................................................................... 1 Input Voltage Range ................................................................... 22 General Description ......................................................................... 1 Layout .......................................................................................... 23 Revision History ............................................................................... 2 Input Bias Current Return Path ............................................... 24 Specif icat ions ..................................................................................... 3 Input Protection ......................................................................... 24 Dual-Supply Operation ............................................................... 3 Radio Frequency Interference (RFI) ........................................ 24 Single-Supply Operation ............................................................. 6 Applications Information .............................................................. 25 Absolute Maximum Ratings ............................................................ 9 Precision Strain Gage ................................................................. 25 Thermal Resistance ...................................................................... 9 Differential Drive ....................................................................... 25 ESD Caution .................................................................................. 9 Driving a Cable ........................................................................... 26 Pin Configuration and Function Descriptions ........................... 10 Driving an ADC ......................................................................... 27 Typical Performance Characteristics ........................................... 11 Outline Dimensions ....................................................................... 28 Theory of Operation ...................................................................... 21 Ordering Guide .......................................................................... 28 Architec ture ................................................................................. 21 REVISION HISTORY 7/11Revision 0: Initial Version Rev. 0 Page 2 of 28