CF5762AB0 Datasheet, PDF (9/10 Pages) Nippon Precision Circuits Inc – Analog Chime Clock CMOS IC

CF5762AB0
Dual Pitch Synthesis (DPS)
Separate A and B pitches are processed by reading a
single set of waveform data at slightly varying fre-
quencies to create a chorus effect, to which an enve-
lope functions are added, and then the resulting
pitches are mixed (added) to generate output pitches.
NORMAL
waveform data
Envelope
Shift
CHORUS
waveform data
Pitch A
Pitch B
Envelope
Mixer output
Figure 5. Dual pitch synthesis block diagram
Number of Simultaneous Pitches
There are a maximum of 2 pitches with 2 pitch col- the A and B normal melody (normal waveform) and
ors that can be generated simultaneously. These are chorus (chorus waveform) pitches.
Dynamic Range
The range of pitches stored in Note-ROM is C3 to C6.
Waveform Data
There are 2 waveform data sets that are stored in
Wave-ROM: Wave data 0 and Wave data 1. When
WSEL is LOW or open circuit, pitch synthesis uses
the preassigned waveform data sets. When WSEL is
HIGH, all pitch synthesis uses the wave data 1 set.
If the waveform data assignment is changed mid
melody, subsequent pitch sounds generated will
change because the data waveform used for pitch
synthesis changes immediately in response to
WSEL, even during pitch synthesis.
NIPPON PRECISION CIRCUITS INC.—9