Alternative Parts


Features and Benefits

  • Dual integrated I/Q demodulator
  • 16 phase select options on each output (22.5° per step)
  • Quadrature demodulation accuracy
    • Phase accuracy: ±0.1°
    • Amplitude balance: ±0.05 dB
  • Bandwidth
    • 4 × LO: 10 kHz to 200 MHz
    • RF: dc to 50 MHz
    • Baseband: determined by external filtering
  • Output dynamic range: 159 dB/Hz
  • LO drive > 0 dBm (50 Ω); 4 × LO > 1 MHz
  • Supply: ±5 V
  • Power consumption: 190 mW/channel (380 mW total)
  • Power-down

Product Details

The AD8333 is a dual-phase shifter and I/Q demodulator that enables coherent summing and phase alignment of multiple analog data channels. It is the first solid-state device suitable for beamformer circuits, such as those used in high performance medical ultrasound equipment featuring CW Doppler. The RF inputs interface directly with the outputs of the dual-channel, low noise preamplifiers included in the AD8332.

A divide-by-4 circuit generates the internal 0° and 90° phases of the local oscillator (LO) that drive the mixers of a pair of matched I/Q demodulators.

The AD8333 can be applied as a major element in analog beamformer circuits in medical ultrasound equipment.

The AD8333 features an asynchronous reset pin. When used in arrays, the reset pin sets all the LO dividers in the same state. Sixteen discrete phase rotations in 22.5° increments can be selected independently for each channel. For example, if Channel 1 is used as a reference and the RF signal applied to Channel 2 has an I/Q phase lead of 45°, Channel 2 can be phase aligned with Channel 1 by choosing the correct code.

Phase shift is defined by the output of one channel relative to another. For example, if the code of Channel 1 is adjusted to 0000 and that of Channel 2 to 0001 and the same signal is applied to both RF inputs, the output of Channel 2 leads that of Channel 1 by 22.5°.

The I and Q outputs are provided as currents to facilitate summation. The summed current outputs are converted to voltages by a high dynamic-range, current-to-voltage (I-V) converter, such as the AD8021, configured as a transimpedance amplifier. The resultant signal is then applied to a high resolution ADC, such as the AD7665 (16 bit/570 kSPS).

The two I/Q demodulators can be used independently in other nonbeamforming applications. In that case, a transimpedance amplifier is needed for each of the I and Q outputs, four in total for the dual I/Q demodulator.

The dynamic range is 159 dB/Hz at each I and Q output, but the following transimpedance amplifier is an important element in maintaining the overall dynamic range, and attention needs to be paid to optimal component selection and design.

The AD8333 is available in a 32-lead LFCSP (5 mm × 5 mm) package for the industrial temperature range of −40°C to +85°C.


  • Medical imaging (CW ultrasound beamforming)
  • Phased array systems (radar and adaptive antennas)
  • Communication receivers

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

SPICE Models

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

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


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 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 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.