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  2. A/D Converters (ADC)
  3. Precision A/D Converters
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  5. AD7643

Alternative Parts


Features and Benefits

  • Throughput: 1.25 MSPS
  • INL: ±2 LSB typical, ±3 LSB max; ±8 ppm of full scale
  • 18-bit resolution with no missing codes
  • Dynamic range: 95.5 dB
  • SINAD: 93.5 dB typical @ 20 kHz (VREF = 2.5 V)
  • THD: −112 dB typical @ 20 kHz (VREF = 2.5 V)
  • No pipeline delay (SAR architecture)
  • Pb-free, 48-lead LQFP and 48-lead LFCSP
  • Pin compatible with the AD7641 and other PulSAR ADC’s
  • 2.048 V internal reference: typical drift 10 ppm/°C; TEMP output
  • Differential input range: ±VREF
    (VREF up to 2.5 V)
  • Parallel (18-, 16-, or 8-bit bus) and serial 5 V/3.3 V/2.5 V interface
  • SPI®/QSPI/MICROWIRE/DSP compatible
  • Single 2.5 V supply operation
  • Power dissipation
    • 65 mW typical @ 1.25 MSPS with internal REF
    • 2 μW in power-down mode

Product Details

The AD7643 is an 18-bit, 1.25 MSPS, charge redistribution SAR, fully differential, analog-to-digital converter (ADC) that operates from a single 2.5 V power supply. The part contains a high speed, 18-bit sampling ADC, an internal conversion clock, an internal reference (and buffer), error correction circuits, and both serial and parallel system interface ports. The part has no latency and can be used in asynchronous rate applications. The AD7643 is hardware factory calibrated and tested to ensure ac parameters, such as signal-to-noise ratio (SNR), in addition to the more traditional dc parameters of gain, offset, and linearity. The AD7643 is available in Pb-free only packages with operation specified from −40°C to +85°C.


  1. Fast Throughput. The AD7643 is a 1.25MSPS, charge redistribution, 18-bit SAR ADC.
  2. Superior Linearity. The AD7643 has no missing 18-bit code.
  3. Internal Reference. The AD7643 has a 2.048 V internal reference with a typical drift of ±10 ppm/°C and an on-chip TEMP sensor.
  4. Single-Supply Operation. The AD7643 operates from a 2.5 V single supply.
  5. Serial or Parallel Interface. Versatile parallel (18-, 16-, or 8-bit bus) or 2-wire serial interface arrangement compatible with 2.5 V, 3.3 V, or 5 V logic.


  • Medical instruments
  • High speed data acquisition/high dynamic data acquisition
  • Digital signal processing
  • Spectrum analysis
  • Instrumentation
  • Communications
  • ATE

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)

Product Recommendations

AD7643 Companion Parts

Recommended Driver Amplifiers

Recommended External 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.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
AD7643BCPZ Material Declaration Reliability Data 48-Lead LFCSP (7mm x 7mm x 0.85mm w/ EP)
AD7643BCPZRL Material Declaration Reliability Data 48-Lead LFCSP (7mm x 7mm x 0.85mm w/ EP)
AD7643BSTZ Material Declaration Reliability Data 48-Lead LQFP (7mm x 7mm)
AD7643BSTZRL Material Declaration Reliability Data 48-Lead LQFP (7mm x 7mm)
Wafer Fabrication Data

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Sample & Buy

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Buy Now Pricing

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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

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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.