AD8333

Data Sheet DC to 50 MHz, Dual I/Q Demodulator and Phase Shifter AD8333 FEATURES 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 APPLICATIONS Medical imaging (CW ultrasound beamforming) Phased array systems (radar and adaptive antennas) Communication receivers GENERAL DESCRIPTION The AD83331 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° increme...