VCA610

The VCA610 is a wideband, continuously variable, voltage controlled gain amplifier. It provides lineardB gain control with high impedance inputs. It is designed to be used as a flexible gain control element in a variety of electronic systems.

The VCA610 has a gain control range of 80dB (40dB to +40dB) providing both gain and attenuation for maximum flexibility in a small 8-lead SO-8 or plastic dual-in-line package. The broad attenuation range can be used for gradual or controlled channel turn-on and turn-off for applications in which abrupt gain changes can create artifacts or other errors. In addition, the output can be disabled to provide 80dB of attenuation. Group delay variation with gain is typically less than ±2ns across a bandwidth of 1 to 15MHz.

The VCA610 has a noise figure of 3.5dB (with an RS of 200W) including the effects of both current and voltage noise. Instantaneous output dynamic range is 70dB for gains of 0dB to +40dB with 1MHz noise bandwidth. The output is capable of driving 100W. The high speed, 300dB/ms, gain control signal is a unipolar (0 to 2V) voltage that varies the gain linearly in dB/V.

The VCA610 is designed with a very fast overload recovery time of only 200ns. This allows a large signal transient to overload the output at high gain, without obscuring low-level signals following closely behind. The excellent overload recovery time and distortion specifications optimize this device for lowlevel doppler measurements.