Features and Benefits

  • 16-bit resolution and monotonicity
  • Pin selectable NAMUR-compliant ranges
    • 4 mA to 20 mA
    • 3.8 mA to 21 mA
    • 3.2 mA to 24 mA
  • NAMUR-compliant alarm currents
    • Downscale alarm current = 3.2 mA
    • Upscale alarm current = 22.8 mA/24 mA
  • Total unadjusted error (TUE): 0.05% maximum
  • INL error: 0.0035% FSR maximum
  • Output TC: 3 ppm/°C typical
  • Quiescent current: 300 μA maximum
  • Flexible SPI-compatible serial digital interface with Schmitt triggered inputs
  • On-chip fault alerts via FAULT pin or alarm current
  • Automatic readback of fault register on each write cycle
  • Slew rate control function
  • Gain and offset adjust registers
  • On-chip reference TC: 4 ppm/°C maximum
  • Selectable regulated voltage output
  • Loop voltage range: 5.5 V to 52 V
  • Temperature range: −40°C to +105°C
  • TSSOP and LFCSP packages

Product Details

The AD5421 is a complete, loop-powered, 4 mA to 20 mA digital-to-analog converter (DAC) designed to meet the needs of smart transmitter manufacturers in the industrial control industry. The DAC provides a high precision, fully integrated, low cost solution in compact TSSOP and LFCSP packages.

The AD5421 includes a regulated voltage output that is used to power itself and other devices in the transmitter. This regulator provides a regulated 1.8 V to 12 V output voltage. The AD5421 also contains 1.22 V and 2.5 V references, thus eliminating the need for a discrete regulator and voltage reference.

The AD5421 can be used with standard Highway Addressable Remote Transducer (HART®) FSK protocol communication circuitry without any degradation in specified performance. The high speed serial interface is capable of operating at 30 MHz and allows for simple connection to commonly used microprocessors and microcontrollers via a SPI-compatible, 3-wire interface.

The AD5421 is guaranteed monotonic to 16 bits. It provides 0.0015% integral nonlinearity, 0.0012% offset error, and 0.0006% gain error under typical conditions.

The AD5421 is available in a 28-lead TSSOP and a 32-lead LFCSP specified over the extended industrial temperature range of −40°C to +105°C.


  • Industrial Process Control
  • 4 mA to 20 mA loop-powered transmitters
  • Smart transmitters
  • HART network connectivity

Product Lifecycle icon-recommended Recommended for New Designs

This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.

Evaluation Kits (1)

Tools & Simulations

Precision DAC Error Budget Tool

The Precision DAC Error Budget Tool is a web application that calculates the DC Accuracy of precision DAC signal chains. It shows how the static errors accumulate throughout your signal chain to quickly evaluate the design tradeoffs. Calculations include the DC errors introduced by Voltage References, Operation Amplifiers and Precision DACs.

Precision DAC Error Budget Tool

IBIS Models

AD5421 IBIS Model

Reference Designs (3)

Product Recommendations

AD5421 Companion Parts

Recommended Digital Isolators

Recommended Low Power Hart Modem

Recommended Voltage References

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.

PCN-PDN Information

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.

Selecting the Sample button above 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.