CES CEM3394, Quick Start Manual

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CEM3394 uP CONTROLLABLE SYNTHESIZER VOICE
DESCRIPTION
The CEM3394 is a complete analog music synthesizer voice-on-a-chip intended for software control
by a microprocessor system. Included inside the compact 20 pin package is fully temperature
compensated, wide range, voltage controlled oscillator providing triangle, sawtooth, and pulse
waveforms; a voltage controlled mixer for adjusting the balance between the internally generated
VCO waveforms and any external signal; a dedicated four-pole low-pass voltage controlled filter
with voltage controlled resonance; a modulation amount VCA for modulating the filter frequency
by the triangle waveform output of the VCO; and a final VCA for allowing the output to be
enveloped. Envelope control for both the VCF and final VCA may be provided by either a hardware
envelope generator such as the CEM3310, CEM3371, or through software.
Ranging between -4 and +4 volts, all eight control inputs are provided with internal very high
input impedance, low bias current buffers. Thus interface to a microprocessor system may be
accomplished simply with a single DAC, 4051-type CMOS multiplexer, and 8 hold capacitors.
Requiring a bare minimum of other external components, the CEM3394 is ideal for low cost
polyphonic or polytimbric musical instruments featuring rich, analog sound.
FEATURES
•
Low Cost
• Complete synthesizer Voice on a Chip
•
20 Pin DIP Package
• Sample & Hold buffers on-chip for easy interface to a uP
•
Fully temperature compensated VCO
• Independently selectable VCO waveforms
•
Constant Loudness vs Resonance VCF
• Rich Sounding VCF Design
•
Filter FM routing for more Timbres
• Low Noise, Low Feedthrough VCA
•
Few External Components