1. Products
  2. Amplifiers
  3. Operational Amplifiers (Op Amps)
  4. Rail-to-Rail Op Amps
  5. AD8505


Features and Benefits

  • PSRR: 100 dB minimum
  • CMRR: 105 dB typical
  • Very low supply current: 20 μA per amplifier maximum
  • 1.8 V to 5 V single supply or ±0.9 V to ±2.5 V dual supply
  • Rail-to-rail input/output
  • Low noise: 45 nV/√Hz at 1 kHz
  • 2.5 mV offset voltage maximum
  • Very low input bias current: 1 pA typical

Product Details

The AD8505/AD8506/AD8508 are single, dual, and quad micro-power amplifiers featuring rail-to-rail input/output swings while operating from a single 1.8 V to 5 V power supply or from dual ±0.9 V to ±2.5 V power supplies. Using a new circuit technology, these amplifiers offer zero input crossover distortion (excellent PSRR and CMRR performance) and low bias current while operating with a supply current of less than 20 μA per amplifier. This amplifier family offers the lowest noise in its power class.

This combination of features makes the AD8505/AD8506/AD8508 amplifiers ideal choices for battery-powered applications because they minimize errors due to power supply voltage variations over the lifetime of the battery and maintain high CMRR even for a rail-to-rail input op amp. Remote battery-powered sensors, handheld instrumentation, consumer equipment, hazard detection (for example, smoke, fire, and gas), and patient monitors can benefit from the features of the AD8505/AD8506/AD8508 amplifiers.

The AD8505/AD8506/AD8508 are specified for both the industrial temperature range of −40°C to +85°C and the extended industrial temperature range of −40°C to +125°C. The AD8505 single ampli-fier is available in a tiny 5-lead SOT-23 package. The AD8506 dual amplifier is available in 8-lead MSOP and 8-ball WLCSP packages. The AD8508 quad amplifier is available in 14-lead TSSOP and 14-ball WLCSP packages. The AD8505/AD8506/AD8508 are members of a growing series of zero crossover distortion op amps offered by Analog Devices, Inc., including the ADA4505-1/ ADA4505-2/ADA4505-4, that operate from a single 1.8 V to 5 V supply or from dual ±0.9 V to ±2.5 V power supplies.


  • Pressure and position sensors
  • Remote security
  • Bio sensors
  • IR thermometers
  • Battery-powered consumer equipment
  • Hazard detectors
  • Product Lifecycle icon-recommended 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)

    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:


    SPICE Model

    Design Tool

    Analog Filter Wizard

    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.

    Analog Photodiode Wizard

    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.

    Design Resources

    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.View our quality and reliability program and certifications for more information.

    Part Number Material Declaration Reliability Data Pin/Package Drawing CAD Symbols, Footprints & 3D Models
    AD8505ACBZ-R7 Material Declaration Reliability Data 6-Ball WLCSP (0.905mm x 1.385mm)
    AD8505ACBZ-RL Material Declaration Reliability Data 6-Ball WLCSP (0.905mm x 1.385mm)
    AD8505ARJZ-R7 Material Declaration Reliability Data 5-Lead SOT-23
    Wafer Fabrication Data

    PCN-PDN Information

    Select a model from the dropdown below to subscribe to PCN/PDN notifications and view past notifications as well.

    Sample & Buy

    Ordering FAQs

    See our Ordering FAQs for answers to questions about online orders, payment options and more.


    Buy Now Pricing

    (**) Displayed Buy Now Price and Price Range is based on small quantity orders.


    List Pricing

    (*)The 1Ku 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. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.


    Lead Times

    Please see the latest communication from our CCO regarding lead times.



    A Sample link will be shown above, next to the part, only for parts that are included in our sample program. Selecting the Sample button will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.

    Price Table Help


    Evaluation Boards

    Pricing displayed is based on 1-piece.

    Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.

    Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.