VCA2612Y/250

具有低噪声前置放大器的双路可变增益放大器 48-TQFP -40 to 85

The VCA2612 is a highly integrated, dual receive channel, signal processing subsystem. Each channel of the product consists of a low noise preamplifier LNP and a Variable Gain Amplifier VGA. The LNP circuit provides the necessary connections to implement Active Termination AT, a method of cable termination which results in up to 4.6dB noise figure improvement. Different cable termination characteristics can be accommodated by utilizing the VCA2612\x92s switchable LNA feedback pins. The LNP has the ability to accept both differential and single-ended inputs, and generates a differential output signal. The LNP provides strappable gains of 5dB, 17dB, 22dB, and 25dB.

The output of the LNP can be accessed externally for further signal processing, or fed directly into the VGA. The VCA2612\x92s 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 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.

The VCA2612 also features low crosstalk and outstanding distortion performance. The combination of low noise and gain range programmability make the VCA2612 a versatile building block in a number of applications where noise performance is critical. The VCA2612 is available in a TQFP-48 package.