AD8331ARQZ (ANALOG DEVICES)

The AD8331ARQZ is an Ultralow Noise Variable Gain Amplifier with Preamplifier and Programmable RIN optimized for ultrasound systems. This VGA is used as low noise variable gain element at frequencies up to 120MHz. The LNA gain is 19dB 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 48dB 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 50dB/V for control voltages between 40mV and 1V. 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 low output-referred noise of the VGA is advantageous in driving high speed differential ADCs.