Features and Benefits
- Low Supply Current: 250 µA max
- Very Low Input Bias Current: 1 pA max
- Low Offset Voltage: 750 µV max
- Single-supply Operation: 5 V to 26 V
- Dual-supply Operation: ±2.5 V to ±13 V
- Rail-to-rail Output
- Unity Gain Stable
- No Phase Reversal
The AD8641/AD8642/AD8643 are low power, precision JFET input amplifiers featuring extremely low input bias current and rail-to-rail output. The ability to swing nearly rail-to-rail at the input and rail-to-rail at the output enables designers to buffer CMOS DACs, ASICs, and other wide output swing devices in single-supply systems. The outputs remain stable with capacitive loads of more than 500 pF.
The AD8641/AD8642/AD8643 are suitable for applications utilizing multichannel boards that require low power to manage heat. Other applications include photodiodes, ATE reference level drivers, battery management, and industrial controls.
The AD8641/AD8642/AD8643 are fully specified over the extended industrial temperature range of –40°C to +125°C. The AD8641 is available in 5-lead SC70 and 8-lead SOIC lead-free packages. The AD8642 is available in 8-lead MSOP and 8-lead SOIC lead-free packages. The AD8643 is available in 14-lead SOIC and 16-lead, 3 mm × 3 mm, LFCSP lead-free packages.
- Line-/battery-powered instruments
- Photodiode amplifiers
- Precision current sensing
- Medical instrumentation
- Industrial controls
- Precision filters
- Portable audio
Markets & Technology
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
The universal precision op amp evaluation boards have been designed and optimized for many circuit configurations allowing the users to best suit their applications. These boards are all RoHs compliant. See references below on what board to order by lead count and package.
- EVAL-PRAOPAMP-2CPZ (dual 8-lead LFCSP) CP-8
- EVAL-PRAOPAMP-2RMZ (dual 8-lead MSOP) RM-8
- EVAL-PRAOPAMP-2RZ (dual 8-lead SOIC) R-8
Tools & Simulations
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
Models for the following parts are available in LTspice:
Use the Analog Filter Wizard to design low-pass, high-pass, or band-pass filters with actual op amps in minutes. As you progress through the design process, you can observe the characteristics of your filter design from ideal specifications to real world circuit behavior. Quickly evaluate the tradeoffs in op amp specifications - including gain-bandwidth, noise, and supply current – to determine the best filter design for your requirements.
Use Photodiode Wizard to design a transimpedance amplifier circuit to interface with a photodiode. Select a photodiode from the library included in the tool, or enter custom photodiode specifications. Quickly observe tradeoffs between Bandwidth, Peaking (Q), and ENOB/SNR. Modify circuit parameters, and immediately see results in plots for pulse response, frequency response, and noise gain.
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
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.