Datasheet AD8426 (Analog Devices)

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Wide Supply Range, Rail-to-Rail Output Instrumentation Amplifier AD8426 FEATURES CONNECTION DIAGRAM 2 channels in a small, 4 mm × 4 mm LFCSP S T1 T2 S +V OU OU –V LFCSP package has no metal pad 16 15 14 13 More routing room AD8426 No current leakage to pad –IN1 1 12 –IN2 Gain set with 1 external resistor RG1 2 11 RG2 Gain range: 1 to 1000 RG1 3 10 RG2 Input voltage goes below ground +IN1 4 9 +IN2 Inputs protected beyond supplies Very wide power supply range 5 6 7 8 Single supply: 2.2 V to 36 V
01
S 1 2 S
0
F F
0-
Dual supply: ±1.35 V to ±18 V +V –V
49
RE RE
09
Bandwidth (G = 1): 1 MHz
Figure 1.
CMRR (G = 1): 80 dB minimum Input noise: 24 nV/√Hz Table 1. Instrumentation Amplifiers by Category1 Typical supply current (per amplifier): 350 μA General- Zero Military Low High Speed Specified temperature range: −40°C to +125°C 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. instrumentation amplifier that requires only one external The two amplifiers are arranged in a logical way so that typical resistor to set any gain from 1 to 1000. application circuits have short routes and few vias. Unlike most The AD8426 is designed to work with a variety of signal chip scale packages, the AD8426 does not have an exposed metal voltages. A wide input range and rail-to-rail output allow the pad on the bottom of the part, which frees additional space for signal to make full use of the supply rails. Because the input routing and vias. The AD8426 offers two in-amps in the equivalent range can also go below the negative supply, small signals near board space of a typical MSOP package. 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 The robust AD8426 inputs are designed to connect to real- can easily handle ±10 V signals. With its space-saving LFCSP world sensors. In addition to its wide operating range, the package and 125°C temperature rating, the AD8426 thrives in AD8426 can handle voltages beyond the rails. For example, tightly packed, zero airflow designs. 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.
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Document Outline FEATURES APPLICATIONS CONNECTION DIAGRAM GENERAL DESCRIPTION TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS DUAL-SUPPLY OPERATION Dynamic Performance Specifications SINGLE-SUPPLY OPERATION Dynamic Performance Specifications ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS THEORY OF OPERATION ARCHITECTURE GAIN SELECTION REFERENCE TERMINAL INPUT VOLTAGE RANGE LAYOUT Package Considerations Hidden Paddle Package Common-Mode Rejection Ratio over Frequency Power Supplies References INPUT BIAS CURRENT RETURN PATH INPUT PROTECTION RADIO FREQUENCY INTERFERENCE (RFI) APPLICATIONS INFORMATION PRECISION STRAIN GAGE DIFFERENTIAL DRIVE Differential Output Using Both AD8426 Amplifiers 2-Channel Differential Output Using a Dual Op Amp Tips for Best Differential Output Performance DRIVING A CABLE DRIVING AN ADC OUTLINE DIMENSIONS ORDERING GUIDE