AS3350 ALFA - Dual Voltage Controlled State Variable Filter (VCF) IC (PDIP-16)

The AS3350 is a dual voltage controlled state-variable filter intended for electronic musical instruments and other signal processing applications. Each filter provides both voltage control of center/cut-off frequency over more than 12 octaves and voltage control of Q from 1/2 to greater than 40. All control scales are exponential, allowing for easier control of the parameters over their wide range. Although the two filters are completely independent, they may be easily interconnected to form a wide variety of filter responses.
Each filter also provides two signal inputs: For signals applied to the fixed gain input, the output will remain constant as the Q is varied, while for signals applied to the variable gain input, the output decreases as Q is increased. The input signal may be proportioned between these two inputs to provide any desired characteristic.
Finally, each filter provides two simultaneous outputs, making directly available low-pass and band-pass, or band-pass and high-pass responses depending upon where the input signal is applied.
Able to operate over a wide supply range, the versatile AS3350 allows new and unique filter responses to be created with a high degree of voltage control over the defining parameters.

- two Independent state variable filters 
- separate frequency and Q control Inputs for each channel
- wide frequency sweep and Q control range
- exponential control scales for both frequency and Q
- two simultaneous outputs on each: Low-Pass and 
  Band-Pass or Band-Pass and High-Pass possible
- two simultaneous inputs for each: fixed gain and
  variable gain
- configurable Into many V.C. filters
- wide supply range: ±3V to ±16V

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