Analog Devices AD9279 Evaluation Board AD9279-65EBZ AD9279-65EBZ データシート

製品コード
AD9279-65EBZ
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Octal LNA/VGA/AAF/ADC 
and CW I/Q Demodulator
 
AD9279
 
 
Rev. 0 
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responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other 
rights of third parties that may result from its use. Specifications subject to change without notice. No 
license is granted by implication or otherwise under any patent or patent rights of Analog Devices. 
Trademarks and registered trademarks are the property of their respective owners. 
 
 
 
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700 
www.analog.com
 
Fax: 781.461.3113 
©2010 Analog Devices, Inc. All rights reserved. 
FEATURES 
8 channels of LNA, VGA, AAF, ADC, and I/Q demodulator 
Low power: 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: <2 μs 
Overload recovery: <10 ns 
Low noise preamplifier (LNA) 
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 
Variable gain amplifier (VGA) 
Attenuator range: −45 dB to 0 dB 
Postamp gain (PGA): 21 dB/24 dB/27 dB/30 dB 
Linear-in-dB gain control 
Antialiasing filter (AAF) 
Programmable second-order LPF from 8 MHz to 18 MHz 
Programmable HPF 
Analog-to-digital converter (ADC) 
SNR: 70 dB, 12 bits up to 80 MSPS 
Serial LVDS (ANSI-644, low power/reduced signal) 
CW mode I/Q demodulator 
Individual programmable phase rotation 
Output dynamic range per channel: >160 dBc/√Hz 
Output-referred SNR: 155 dBc/√Hz, 1 kHz offset, −3 dBFS 
GENERAL DESCRIPTION 
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. 
FUNCTIONAL BLOCK DIAGRAM 
094
23-
0
01
AAF
12-BIT
ADC
VGA
LNA
SERIAL
LVDS
I/Q
DEMODULATOR
8 CHANNELS
SERIAL
PORT
INTERFACE
DATA
RATE
MULTIPLIER
REFERENCE
LO
GENERATION
LO-A TO LO-H
LOSW-A TO LOSW-H
LI-A TO LI-H
LG-A  TO LG-H
DOUTA+ TO DOUTH+
DOUTA– TO DOUTH–
FCO+
DRVDD
CL
K–
CLK+
SD
IO
SC
L
K
CS
B
GP
O[0
:3
]
RB
IAS
VR
EF
CW
Q
+
CW
Q
CW
I+
CW
I–
GA
IN
GA
IN
+
4L
O
4L
O
+
RE
S
E
T
STBY
PDWN
AVDD2
AVDD1
FCO–
DCO+
DCO–
 
Figure 1.