The AD9670 is designed for low cost, low power, small size, andease of use for medical ultrasound applications. It contains eightchannels of a VGA with an LNA, a CW harmonic rejection I/Qdemodulator with programmable phase rotation, an antialiasingfilter, an ADC, and a digital demodulator and decimator for dataprocessing and bandwidth reduction.

Each channel features a maximum gain of up to 52 dB, a fullydifferential signal path, and an active input preamplifier termination.The channel is optimized for high dynamic performance andlow power in applications where a small package size is critical.

The LNA has a single-ended-to-differential gain that is selectablethrough the serial port interface (SPI). Assuming a 15 MHz noisebandwidth (NBW) and a 21.6 dB LNA gain, the LNA input SNRis 94 dB. In CW Doppler mode, each LNA output drives an I/Qdemodulator that has independently programmable phaserotation with 16 phase settings.

Power-down of individual channels is supported to increasebattery life for portable applications. Standby mode allows quickpower-up for power cycling. In CW Doppler operation, theVGA, antialiasing filter, and ADC are powered down. The ADCcontains several features designed to maximize flexibility andminimize system cost, such as a programmable clock, dataalignment, and programmable digital test pattern generation.The digital test patterns include built-in fixed patterns, built-inpseudorandom patterns, and custom user-defined test patternsentered via the SPI.

Applications

• Medical imaging/ultrasound
• Nondestructive testing (NDT)

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.