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, see the AD8331/AD8332/AD8334 datasheet.
Applications
Features and Benefits
| AmplifiersReference Designs |
| Document | note |
| AD8331/AD8332/AD8334: Ultralow Noise VGAs with Preamplifier and Programmable RIN Data Sheet (Rev. I) | PDF 1.91 M |
| Document | note |
| Part Number | Package | Packing Qty | Temp Range | Price 100-499 | Price 1000+ | RoHS |
|---|---|---|---|---|---|---|
| AD8331ARQZ Production | 20 ld QSOP | OTH 56 | -40 to 85C | 6.05 | 5.45 | Y |
| AD8331ARQZ-R7 Production | 20 ld QSOP | REEL 1000 | -40 to 85C | 6.05 | 5.45 | Y |
| AD8331ARQZ-RL Production | 20 ld QSOP | REEL 2500 | -40 to 85C | 6.05 | 5.45 | Y |
| Part Number | Description | Price | RoHS |
|---|---|---|---|
| AD8331-EVALZ | Evaluation Board | 82.38 | Y |
