AD9279 Octal LNA/VGA/AAF/ADC and CW I/Q Demodulator

The AD9279 is designed for low cost, low power, small size, and ease of use for medical ultrasound and automotive radar. It contains eight channels of a variable gain amplifier (VGA) with a low noise preamplifier (LNA), an antialiasing filter (AAF), an analog-to-digital converter (ADC), and an I/Q demodulator with programmable phase rotation.

Each channel features a variable gain range of 45 dB, a fully differential signal path, an active input preamplifier termination, and a maximum gain of up to 52 dB. The channel is optimized for high dynamic performance and low power in applications where a small package size is critical.

The LNA has a single-ended-to-differential gain that is selectable through the SPI. Assuming a 15 MHz noise bandwidth (NBW) and a 21.3 dB LNA gain, the LNA input SNR is roughly 94 dB. In CW Doppler mode, each LNA output drives an I/Q demod-ulator that has independently programmable phase rotation with 16 phase settings.

Power-down of individual channels is supported to increase battery life for portable applications. Standby mode allows quick power-up for power cycling. In CW Doppler operation, the VGA, AAF, and ADC are powered down. The ADC contains several features designed to maximize flexibility and minimize system cost, such as a programmable clock, data alignment, and programmable digital test pattern generation. The digital test patterns include built-in fixed patterns, built-in pseudo random patterns, and custom user-defined test patterns entered via the serial port interface.

Features and Benefits
  • Lowpower : 141 mW per channel, TGC mode, 40 MSPS;
    60 mW per channel, CW mode
  • 10 mm × 10 mm, 144-ball CSP-BGA
  • TGC channel input-referred noise: 0.8 nV/√Hz, max gain
  • Flexible power-down modes
  • Fast recovery from low power standby mode: <2us
  • Overload recovery: <10 ns
  • Input-referred noise: 0.75 nV/√Hz , gain = 21.3 dB
  • Programmable gain: 15.6 dB/17.9 dB/21.3 dB
  • 0.1 dB compression: 1000 mV p-p/750 mV p-p/450 mV p-p
  • Dual-mode active input impedance matching
  • Bandwidth (BW) > 100 MHz
  • Attenuator range: −45 dB to 0 dB
  • Postamp gain (PGA): 21 dB/24 dB/27 dB/30 dB
  • Linear-in-dB gain control
  • Programmable second-order LPF from 8 MHz to 18 MHz
  • Programmable HPF
  • SNR: 70 dB, 12 bits up to 80 MSPS
  • Serial LVDS (ANSI-644, Low power/reduced signal)
  • Individual programmable phase rotation
  • Output dynamic range per channel: >160 dBc/√Hz
  • Output-referred SNR: 155 dBc/√Hz, 1kHz offset, -3dBFS
Application Specific
Data Sheets
Documentnote
AD9279: Octal LNA/VGA/AAF/ADC and CW I/Q Demodulator (Rev. 0)PDF 964 kB
Order Information
Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
AD9279BBCZ Production144 ball CSPBGA (10x10x1.4mm)OTH 184-40 to 85C68.2458Y
Evaluation Boards
Part NumberDescriptionPriceRoHS
AD9279-65EBZEvaluation Board250Y
AD9279-80KITZEvaluation Board1100Y
Reference Materials
AD9279: Octal LNA/VGA/AAF/ADC and CW I/Q Demodulator (Rev. 0) ad9279
AD9279:八通道LNA/VGA/AAF/ADC与CW I/Q解调器 (Rev. 0) ad9279
MS-2210:高速ADC的电源设计 ad9861