The VCA2619s VGA section consists of two parts: the Voltage Controlled Attenuator (VCA) and the Programmable Gain Amplifier (PGA). The gain and gain range of the PGA can be digitally programmed. The combination of these two programmable elements results in a variable gain ranging from 0dB up to a maximum gain as defined by the user through external connections. The single-ended unity gain input buffer provides predictable high input impedance. The output of the VGA can be used in either a single-ended or differential mode to drive high-performance Analog-to- Digital (A/D) converters. A separate power-down pin reduces power consumption.