INTRODUCTION
SN66090 is a 90 seconds single chip 4-channel voice synthesizer IC which contains I/O ports and a tiny controller. By programming through the tiny controller, user’s applications including section combination, trigger modes, output status, high performance melody, multiple voices, and other logic functions can be implemented.

FEATURES
♦ Single power supply 2.4V – 5.1V
♦ Built in a tiny controller
♦ 90 seconds voice capacity are provided
♦ One 4-bit input port, two 4-bit I/O ports and one 4-bit output port are provided
♦ 128*4 bits RAM are provided
♦ Maximum 64k program ROM is provided
♦ Readable ROM code data
♦ Built in a high quality speech synthesizer
♦ Four independent voice channels
♦ Adaptive playing speed from 4k-40kHz is provided for all 4 channels individually
♦ Automatic repetition for every channel
♦ A 6-bit*8-bit Multiplier is embed to modulate the volume of synthesized voices
♦ Two digital mixers (with saturation control) are provided
♦ Two 8-bit current output DA converters (Channel 1 + Channel 2 → DA1, Channel 3 + Channel 4 → DA2 )
♦ System clock: 2M Hz ( R-type or Crystal Option)