GENERAL DESCRIPTION The AD9674 is designed for low cost, low power, small size, and ease of use for medical ultrasound. It contains eight channels of a VGA with an LNA, a CW harmonic rejection I/Q demodulator with programmable phase rotation, an AAF, an ADC, a digital HPF, and RF decimation by 2. FEATURES 8 channels of LNA, VGA, AAF, ADC, and digital RF decimator Low power: 150 mW per channel, TGC mode, 40 MSPS; 62.5 mW per channel, CW mode; <30 mW in power-down Time gain compensation (TGC) channel input referred noise: 0.82 nV/√Hz, maximum gain Flexible power-down modes Fast recovery from low power standby mode: <2 μs Low noise preamplifier (LNA) Input referred noise voltage: 0.78 nV/√Hz, gain = 21.6 dB Programmable gain: 15.6 dB/17.9 dB/21.6 dB 0.1 dB compression: 1.00 V p-p/ 0.75 V p-p/0.45 V p-p Flexible active input impedance matching Variable gain amplifier (VGA) Attenuator range: 45 dB, linear in dB gain control Postamplifier gain (PGA): 21 dB/24 dB/27 dB/30 dB Antialiasing filter (AAF) Programmable second-order low-pass filter (LPF) from 8 MHz to 18 MHz or 13.5 MHz to 30 MHz and high-pass filter (HPF) Analog-to-digital converter (ADC) Signal-to-noise ratio (SNR): 75 dB, 14 bits up to 125 MSPS Configurable serial low voltage differential signaling (LVDS) Continuous wave (CW) Doppler mode harmonic rejection I/Q demodulator Individual programmable phase rotation Dynamic range per channel: >160 dBFS/√Hz Close in SNR: 156 dBc/√Hz, 1 kHz offset, −3 dBFS input Radio frequency (RF) digital HPF and decimation by 2 10 mm × 10 mm, 144-ball CSP_BGA APPLICATIONS Medical imaging/ultrasound Nondestructive Testing (NDT)
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