Multimedia ICs
Audio digital delay (KARAOKE echo)
BU9252S / BU9252F
The BU9252S and BU9252F are digital delays specifically for Karaoke systems. Each has an internal sample hold
circuit, an 8-bit A / D and D / A converter and 2kB SRAM, and allows for the selection of one of eight delay times just
by attaching an inexpensive ceramic resonator.
A digital echo system can be formed by using either of these ICs together with the BA7725S or BA7725FS.
•Applications
Karaoke echo system
Electronic circuits that require signal delays
•Features
1) Internal digital delay circuit.
2) Internal 8-bit A / D converter. Sample rate. (14.22kHz
when fOSC = 455kHz).
3) Internal 2k bytes data SRAM.
4) Internal 8-bit D / A converter.
5) CMOS design for low power consumption.
6) Internal sample hold circuit.
7) Internal feedback resistors and capacitors for oscilla-
tor circuits.
•Block diagram
TEST CIRCUIT
8 × 2k SRAM
ADDRESS COUNTER
AND
MAIN TIMING
1