The AD8021 is an exceptionally high performance, high speed voltage feedback amplifier that can be used in 16-bit resolution systems. It is designed to have both low voltage and low current noise (2.1 nV/√Hz typical and 2.1 pA/√Hz typical) while operating at the lowest quiescent supply current (7 mA @ ±5 V) among today's high speed, low noise op amps. The AD8021 operates over a wide range of supply voltages from ±2.25 V to ±12 V, as well as from single 5 V supplies, making it ideal for high speed, low power instruments. An output disable pin allows further reduction of the quiescent supply current to 1.3 mA.
The AD8021 is both technically superior and priced considerably less than comparable amps drawing much higher quiescent current. The AD8021 is a high speed, general-purpose amplifier, ideal for a wide variety of gain configurations, and can be used throughout a signal processing chain and in control loops. The AD8021 is available in both standard 8-lead SOIC and MSOP packages in the industrial temperature range of -40°C to +85°C.
|Title||Content Type||File Type|
|AD8021: Low Noise, High Speed Amplifier for 16-Bit Systems Data Sheet (Rev F, 05/2006) (pdf, 579 kB)||Data Sheets|
|AN-649: Using the Analog Devices Active Filter Design Tool (pdf, 5301 kB)||Application Notes|
|AN-357: Operational Integrators (pdf, 272 kB)||Application Notes|
|AN-581: Biasing and Decoupling Op Amps in Single Supply Applications (pdf, 166 kB)||Application Notes|
|AN-358: Noise and Operational Amplifier Circuits (pdf, 593 kB)||Application Notes|
|AN-356: User's Guide to Applying and Measuring Operational Amplifier Specifications (pdf, 538 kB)||Application Notes|
AN-402: Replacing Output Clamping Op Amps with Input Clamping Amps
(pdf, 55 kB)
So far most clamping amplifiers have relied upon an output clamping architecture and are called output clamp amps (OCAs). A new architecture called an input clamp amp (ICA) offers superior clamping accuracy and lower distortion.
AN-417: Fast Rail-to-Rail Operational Amplifiers Ease Design Constraints in Low Voltage High Speed Systems
(pdf, 228 kB)
Movement towards lower power supply voltages is driven by the demand that systems consume less and less power coupled with the desire to reduce the number of power supply voltages in the system. The following applications are discussed: Single-Ended and Differential Input ADC Input Circuits, Video Line Driver, Active Filter, HDSL Transceiver, and Transformer Drive Circuits.
|AN-257: Careful Design Tames High Speed Op Amps (pdf, 611 kB)||Application Notes|
|AN-253: Find Op Amp Noise with Spreadsheet (pdf, 77 kB)||Application Notes|
|AN-202: An IC Amplifier User’s Guide to Decoupling, Grounding, and Making Things Go Right for a Change (pdf, 76 kB)||Application Notes|
|CN-0260: Oversampled SAR ADC with PGA Achieving Greater Than 125 dB Dynamic Range (pdf)||Circuit Note|
|CN-0042: Driving the AD7366/AD7367 Bipolar SAR ADC in Low-Distortion DC-Coupled (pdf, 130 kB)||Circuit Note|
|MT-060: Choosing Between Voltage Feedback and Current Feedback Op Amps (pdf, 62 kB)||Tutorials|
|MT-059: Compensating for the Effects of Input Capacitance on VFB and CFB Op Amps Used in Current-to-Voltage Converters (pdf, 69 kB)||Tutorials|
|MT-058: Effects of Feedback Capacitance on VFB and CFB Op Amps (pdf, 66 kB)||Tutorials|
|MT-056: High Speed Voltage Feedback Op Amps (pdf, 109 kB)||Tutorials|
|MT-053: Op Amp Distortion: HD, THD, THD + N, IMD, SFDR, MTPR (pdf, 104 kB)||Tutorials|
|MT-052: Op Amp Noise Figure: Don't Be Mislead (pdf, 60 kB)||Tutorials|
|MT-050: Op Amp Total Output Noise Calculations for Second-Order System (pdf, 38 kB)||Tutorials|
|MT-049: Op Amp Total Output Noise Calculations for Single-Pole System (pdf, 40 kB)||Tutorials|
|MT-048: Op Amp Noise Relationships: 1/f Noise, RMS Noise, and Equivalent Noise Bandwidth (pdf, 81 kB)||Tutorials|
|MT-047: Op Amp Noise (pdf, 72 kB)||Tutorials|
|MT-033: Voltage Feedback Op Amp Gain and Bandwidth (pdf, 251 kB)||Tutorials|
|MT-032: Ideal Voltage Feedback (VFB) Op Amp (pdf, 65 kB)||Tutorials|
A Stress-Free Method for Choosing High-Speed Op Amps
A decision-tree approach to making the critical decision about high-speed op amp selection, including a look at some helpful tools.
|UG-101: Evaluation Board User Guide (pdf, 189 kB)||User Guides|
|Low Power Continuous Wave (CW) Doppler for Portable Ultrasound Systems||Technical Articles||HTML|
|Low-Cost Video Multiplexing Using High-Speed Amplifiers||Analog Dialogue||HTML|
High Speed Op Amp Drives a 16-Bit, 1-MSPS Differential-Input A/D Converter
(Analog Dialogue, Vol. 36, No. 6, November/December 2002)
SAR ADC & Driver Quick-Match Guide
(pdf, 251 kB)
Find drivers for ADI's most popular single-ended and differential SAR ADCs based on your specific application conditions.
|Product Selection Guide|
|High Speed Amplifiers Selection Table (pdf, 77 kB)||Product Selection Guide|
|When high performance and low power make the design, ADI converters make the difference.||Overview||HTML|
|RAQs index||Rarely Asked Questions||HTML|
|What's the difference between, power-down, shutdown, standby, sleep mode or disable?||FAQs/RAQs||HTML|
|Glossary of EE Terms||Glossary||HTML|
|Title||Content Type||File Type|
This calculator converts between standard units of power measurement and signal strength.
|Utilities and Conversions||HTML|
Power Dissipation vs Die Temp
This tool estimates die temperature and power dissipation based on the supply voltages, ambient temperature, load characteristics, and package thermal data.
|Utilities and Conversions||HTML|
This tool will help with the selection, evaluation and troubleshooting of voltage feedback Op-Amps. It uses typical data to model the behavior of a selected amplifier. It allows a user to select an amplifier, configure a circuit, apply a signal and evaluate the performance. It is useful for checking an amplifier's spec's such as Bandwidth, Slew Rate, Input/Output Range, Gain Error, Load Current, Stability Issues and DC Errors in a given circuit.
|ADIsim Design/Simulation Tools||HTML|
OpAmp Error Budget Calculator
An online tool to illustrate range, gain and accuracy issues in simple opamp buffers.
|Amplifier Error Budget Analysis||HTML|
An applet for demonstrating stability effects in opamp buffers.
|AD8021 SPICE Macro-Model||SPICE Models||HTML|
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.