The AD8331 is a single channel, ultralow noise, linear-in-dB, variable gain amplifier (VGA). Optimized for ultrasound systems, it is usable as a low noise variable gain element at frequencies up to 120 MHz.
Included is an ultralow noise preamplifier (LNA), an X-AMP® VGA with 48 dB of gain range, and a selectable gain postamplifier with adjustable output limiting. The LNA gain is 19 dB with a single-ended input and differential outputs. Using a single resistor, the LNA input impedance can be adjusted to match a signal source without compromising noise performance.
The 48 dB gain range of the VGA makes these devices suitable for a variety of applications. Excellent bandwidth uniformity is maintained across the entire range. The gain control interface provides precise linear-in-dB scaling of 50 dB/V for control voltages between 40 mV and 1 V. Factory trim ensures excellent part-to-part and channel-to-channel gain matching. Differential signal paths result in superb second- and third-order distortion performance and low crosstalk.
The operating temperature range is -40°C to +85°C. The AD8331 is available in a 20-lead QSOP package.
The AD8331 is a single version of the dual AD8332 and quad AD8334.
For information on specs, please see the AD8331/AD8332 datasheet.
|Title||Content Type||File Type|
|AD8331/AD8332/AD8334: Ultralow Noise VGAs with Preamplifier and Programmable RIN Data Sheet (Rev G, 10/2010) (pdf, 861 kB)||Data Sheets|
|CN-0096: High Frequency Variable Gain Amplifier Extends the Dynamic Range of a 10-Bit, 65 MSPS ADC to Greater Than 100 dB (pdf, 183 kB)||Circuit Note|
|Design and Operation of Automatic Gain Control Loops for Receivers in Modern Communication Systems (pdf, 129 kB)||Tutorials|
How Ultrasound System Considerations Influence Front-End Component Choice
by Eberhard Brunner, Analog Devices, Inc.
(Analog Dialogue Vol. 36, May-July 2002)
|Variable Gain Amplifier Selection Table (pdf, 68 kB)||Product Selection Guide|
ADT7301: Accurate, SPI-Compatible Temperature Sensor in SOT Package
(analogZone September 1, 2003)
RF Source Booklet
(PDF, 4353 kB)
RF IC Product Overview - Version P (02/2014)
|Leading Inside Advertorials: Solving Dynamic Range Problems in Analog Systems (pdf, 75 kB)||Overview|
|What are Variable Gain Amplifiers (VGA's) and how are they used?||FAQs/RAQs||HTML|
|RAQs index||Rarely Asked Questions||HTML|
|Glossary of EE Terms||Glossary||HTML|
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