ALFA RPAR AS3310 ADSR EG IC - CEM3310 Replacement
The AS3310 is a self-contained, precision ADSR type of envelope generator intended for electronic music and other sound generation applications. Attack, decay and release times are exponentially voltage controllable over a wide range, and the sustain level is linearly voltage controllable from 0 to 100% of the peak voltage Vp. All four control Inputs are Isolated from the rest of the circuitry so that the control pins of tracking units may be simply tied together.
The AS3310 is available in DIP16 thru-hole and SOIC16 SMT configurations
Here is a wonderful Wikipedia page that lists original CEM and SSM chips in synthesizers to help with replacment decisions: https://en.wikipedia.org/wiki/CEM_and_SSM_chips_in_synthesizers