INTEGRATED CIRCUIT FOR GENERATING KEYING ENVELOPE SIGNALS

摘要

INTEGRATED CIRCUIT FOR GENERATING KEYING ENVELOPE SIGNAL A multiplexed electronic organ utilizing a plurality of integrated circuit chips, each chip time division multiplexing selected keying envelope time constant signals from a switched capacitor time constant generator for two alphabetic notes over the entire frequency range of a spinet or for one alphabetic note over the entire frequency range of the manuals and pedals of a console organ. The same integrated circuit chip is used for both spinet or console organs. Each chip contains a multiplexer circuit which isolates the multiplexed keying envelope output signals from the time constant generator and includes as a coupling means a plurality of switching element arranged into groups. Some of the groups are interconnected to provide the keying envelope time constant signal normally intended for one frequency range to the output associated with a different frequency range.