The HMADSR1c is a voltage controlled four stage transient generator (envelope generator).  The device can be configured to provide attack-decay-sustain-release (ADSR), AR or AD envelopes.  The time constants for the attack, decay and release stages can be adjusted from a few milliseconds to several minutes.

The circuit offers a significant improvement over conventional OTA based designs in terms of offset voltage (typically <2mV) and control voltage feedthrough.

Features

• Voltage controlled attack, decay and release times.  Exponential control law.
  
• Voltage controlled sustain level.  Linear control law.
  
• True RC exponential decay and release.
• Linear OR exponential attack phase.
• Very low voltage offset (1.5mV typ.)
• Very low control voltage feed-through.
• +/-12V to +/-15V supplies.
  
• Low external parts count.