TECHNICAL NOTE
Audio Accessory ICs
Karaoke/Surround
Digital Echo
BU9253AS/FS, BU9262AFS
●Description
The Karaoke/Surround Digital Echo IC incorporates a digital delay circuit, an input/output mixing circuit, supporting Karaoke
echo and surround system, all in a single chip.
BU9253AS/FS has functions required by Karaoke echo system, and BU9262AFS has various functions required for
surround / echo system.
●Features
＜BU9253AS/FS＞
1) Digital delay time : 131ms (fCLK = 375kHz)
2) Built-in mixing circuit for adding original sound and echo sound
3) Echo mix ratio settable by DC voltage
4) Built-in amplifier circuit for structuring input/output secondary LPF
5) Microphone mute function (mute of mixing sound of original sound + echo sound)
6) Built-in CR oscillation circuit
＜BU9262AFS＞
1) Digital delay time : 8-stage setting from 9.2ms to 192ms
2) Built-in input/output mixing circuit
3) Built-in feedback, delay volume circuit
4) Built-in input/output LPF
5) Serial interface
6) Auto mute circuit built in (action at power on, mode switching)
7) Built-in auto reset circuit at power on
●Applications
Radio cassette recorder, mini-component and karaoke systems.
●Product lineup
Parameter
Supply voltage
Oscillation frequency
Current consumption
Operating temperature range
Package
Digital delay
Echo level
BU9253AS
4.0V～5.5V
375kHz
6mA
-10～+70℃
SDIP18
Fixed
Fixed
BU9253FS
4.0V～5.5V
375kHz
6mA
-10～+70℃
SSOP-A16
Fixed
Fixed
BU9262AFS
4.5V～5.5V
2MHz
20mA
-10～+70℃
SSOP-A32
Variable
Variable
Ver.B Oct.2005
