AD8475ARMZ Analog Devices Inc, AD8475ARMZ Datasheet
AD8475ARMZ
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AD8475ARMZ Summary of contents
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FEATURES Precision attenuation 0. 0.8 Fully differential or single-ended input/output Differential output designed to drive precision ADCs Drives switched capacitor and Σ-Δ ADCs Rail-to-rail output VOCM pin adjusts output common mode Robust overvoltage protection up to ...
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AD8475 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description........................................................................... 1 Functional Block Diagrams............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 Thermal Resistance ...................................................................... 5 ESD Caution.................................................................................. 5 Pin Configurations and Function Descriptions ........................... 6 ...
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SPECIFICATIONS 0.4, VOCM connected to 2 Table 1. Parameter Test Conditions/Comments DYNAMIC PERFORMANCE −3 dB Small Signal Bandwidth −3 dB Large Signal Bandwidth Slew Rate 2 V step Settling Time to ...
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AD8475 Parameter Test Conditions/Comments POWER SUPPLY Specified Voltage Operating Voltage Range Supply Current Over Temperature −40°C ≤ T TEMPERATURE RANGE Specified Performance Range Operating Range 1 Includes amplifier voltage and current noise, as well as noise of internal resistors. 2 ...
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ABSOLUTE MAXIMUM RATINGS Table 2. Parameter Rating Supply Voltage 11 V Maximum Voltage at Any Input Pin +V Minimum Voltage at Any Input Pin −V Storage Temperature Range −65°C to +150°C Specified Temperature Range −40°C to +85°C Operating Temperature Range ...
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AD8475 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS Table 4. 16-Lead LFCSP Pin Function Descriptions Pin No. Mnemonic Description 1 +IN 0.4x Positive Input for 0.4 Attenuation. 2 +IN 0.8x Positive Input for 0.8 Attenuation 3 −IN 0.8x Negative Input for 0.8 ...
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Table 5. 10-Lead MSOP Pin Function Descriptions Pin No. Mnemonic Description 1 −IN 0.8x Negative Input for 0.8 Attenuation 2 −IN 0.4x Negative Input for 0.4 Attenuation 3 +V Positive Supply S 4 VOCM Output Common-Mode Adjust 5 +OUT Noninverting ...
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AD8475 TYPICAL PERFORMANCE CHARACTERISTICS T = 25° gain = 0. kΩ, RTO, unless otherwise specified LOAD 1000 REPRESENTATIVE SAMPLES 800 600 400 200 0 –200 –400 –600 –800 –1000 –40 –20 ...
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S 0.2 0.4 0.6 0.8 1.0 –40°C +25°C +85°C +105°C +125°C 1.0 0.8 0.6 0.4 0.2 –V S 100 1k 10k 100k R (Ω) LOAD Figure 11. Output Voltage Swing vs. R vs. Temperature, LOAD V = ±5 V ...
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AD8475 0 –1. 0.8 –7.96 – 0.4 –20 –30 –40 –50 1k 10k 100k 1M FREQUENCY (Hz) Figure 17. Small Signal Frequency Response for All Gains V 0 –7.96 –10 –20 –30 –40 1k 10k 100k ...
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C = 0pF 5pF 10pF L –7.96 –10 –20 –30 –40 1k 10k 100k 1M FREQUENCY (Hz) Figure 23. Small Signal Frequency Response for Various Capacitive Loads 0 VOCM = 1V VOCM = ...
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AD8475 V = 100mV p-p OUT 10ns/DIV Figure 29. Small Signal Pulse Response 0pF 5pF 10pF L 10ns/DIV Figure 30. Small Signal Step Response for Various Capacitive Loads ±2.5 ...
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Figure 35. VOCM Small Signal Step Response, V –20 HD2 0.4 HD3 0.4 HD2 0.8 –40 HD3 0.8 –60 –80 –100 –120 –140 0.1 1 FREQUENCY (MHz) Figure 36. Harmonic Distortion ...
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AD8475 – 100kHz HD2, +5V SUPPLY HD3, +5V SUPPLY –40 HD2, ±5V SUPPLY HD3, ±5V SUPPLY –60 –80 –100 –120 –140 p-p) OUT Figure 41. Harmonic Distortion vs. V OUT ...
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FREQUENCY (Hz) Figure 47. Output Balance Error vs. Frequency 100M Rev Page AD8475 ...
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AD8475 TERMINOLOGY 1kΩ 1.25kΩ –OUT +IN AD8475 VOCM –IN +OUT 1.25kΩ 1kΩ Figure 48. Signal and Circuit Definitions Differential Voltage Differential voltage refers to the difference between two node voltages. For example, the output differential voltage (or equivalently, output differential ...
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THEORY OF OPERATION OVERVIEW The AD8475 is a fully differential amplifier, with integrated laser- trimmed resistors, that provides precision attenuating gains of 0.4 and 0.8. The internal differential amplifier of the AD8475 differs from conventional operational amplifiers in that it ...
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AD8475 INPUT VOLTAGE RANGE The AD8475 can measure input voltages that are larger than the supply rails. The internal gain and feedback resistors form a divider, which reduces the input voltage seen by the internal input nodes of the amplifier. ...
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APPLICATIONS INFORMATION TYPICAL CONFIGURATION The AD8475 is designed to facilitate single-ended-to-differential conversion, common-mode level shifting, and precision attenuation of large signals so that they are compatible with low voltage ADCs. Figure 53 shows a typical connection diagram of the AD8475 ...
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AD8475 LOW V IN IMPEDANCE INPUT SOURCE HIGH PERFORMANCE ADC DRIVING The AD8475 is ideally suited for broadband dc-coupled and industrial applications. The circuit in Figure 55 shows an industrial front-end connection for an AD8475 driving an AD7982, a 18-bit, ...
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The differential RC network between the AD8475 output and the ADC provides a single-pole filter that reduces undesirable aliasing effects and high frequency noise. The common-mode bandwidth of the filter is 29.5 MHz (20 Ω, 270 pF), and the differential ...
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AD8475 AD8475 EVALUATION BOARD An evaluation board for the AD8475 is available to facilitate standalone testing of the AD8475 performance and functionality for customer evaluation and system design. The board provides the user flexibility to configure the AD8475 in the ...
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OUTLINE DIMENSIONS PIN 1 INDICATOR 0.80 0.75 0.70 SEATING PLANE IDENTIFIER 3.10 0.30 3.00 SQ 0.25 2.90 0.20 13 0.50 12 BSC EXPOSED 9 8 0.50 TOP VIEW BOTTOM VIEW 0.40 0.30 0.05 MAX 0.02 NOM COPLANARITY 0.08 0.20 REF ...
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... AD8475BRMZ-RL −40°C to +85°C AD8475ARMZ −40°C to +85°C AD8475ARMZ-R7 −40°C to +85°C AD8475ARMZ-RL −40°C to +85°C AD8475-EVALZ RoHS Compliant Part. ©2010–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. ...