VCA610 (Burr-Brown)

[Edu Silva]

I suppose everybody in this list knows this chip and will tell me it
doesn't works well, but I must ask...

Any synth applications for it?

VCA610
Wideband Voltage Controlled Amplifier
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FEATURES 

•WIDE GAIN CONTROL RANGE: 80dB 
•SMALL PACKAGE: 8-pin SOIC or DIP 
•WIDE BANDWIDTH: 30MHz 
•LOW VOLTAGE NOISE: 2.2nV/sqrt(Hz) 
•FAST GAIN SLEW RATE: 300dB/µs 
•EASY TO USE 

APPLICATIONS 

•ULTRASOUND 
•AGC AMPLIFIER 
•ANALYTICAL INSTRUMENTATION 
•SONAR 
•ACTIVE FILTERS 
•LOG AMPLIFIER 
•IF CIRCUITS 
•CCD CAMERAS 

DESCRIPTION

The VCA610 is a wideband, continuously variable, voltage controlled gain
amplifier. It provides linear-dB 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-pin SOIC 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 200(ohm)) 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 100(ohm). The high speed, 300dB/µs, gain
control signal is a unipolar 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 low-level doppler measurements.

DATASHEET:

http://www.burr-brown.com/download/DataSheets/VCA610.pdf

Edu
_____________________
ES2 Audio - Som & Luz
Salvador-Bahia-Brasil