Echo Mode & Surround Mode

Page 4

Add

Low Pass

Filter

AD Converter

DA Converter

Low Pass

Filter

SRAM

Audio In

Audio

out

Echo Mode

ABSOLUTE MAXIMUM RATINGS

( Ta = 25 C, unless otherwise noted )

o

Symbol

Vcc

Icc

Pd

Topr

Tstg

Description

Supply voltage

Supply current

Power dissipation

Operation temperature

Storage temperature

Unit

V

mA

W

C

C

Limits

6.5

100

1.7

-20

75

-25

125

o

o

SM7181 digitize the audio signal through A/D converter and store the value in a First-in- First-out 8Kbits

SRAM. After 3.2RCms of delay time the value store in the SRAM will be read out and reconstruct by

D/A converter then add with the present sound to become an echo signal output. The echo delay is

control by the RC of Pin 2, Pin 3.

SM7181

ECHO

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