HT8972

Voice Echo

Block Diagram

Rev. 1.00

1

December 23, 2008

Features

Applications

General Description

The HT8972 is an echo/surround effect processor. It is

designed for various audio systems including karaoke,

television, sound equipments, etc. The chip consists of

a built-in pre-amplifier, VCO or Voltage Control OSC,

40Kb SRAM, A/D and D/A converters as well as delay

time control logic.

Its built-in 40Kb SRAM can generate delay time effect

and can control the delay time value through the exter-

nal VCO resistor.

The VCO circuit can reduce external components and

make it easy to adjust the delay time.

1 / 2 V C C

A U T O

R E S E T

D I

M O

M I

C L O C K

4 0 K B i t s

R A M

V C O

C O M P

L P F 2

D O 0

D O 1

4 . 7 k W

M O D

D E M

L P F 1

O S C _ O

R E F

V C C

A G N D

D G N D

L P F 1 _ I N

L P F 1 _ O U T

L P F 2 _ O U T

L P F 2 _ I N

O P 2 _ O U T

O P 2 _ I N O P 1 _ I N

O P 1 _ O U T

C C 0

C C 1

4 . 7 k W

v c o