HOLTEK HT8970

HT8970
Voice Echo
Features
·
·
·
·
Operating voltage: 4.5V~5.5V
ADM algorithm
Low noise
- Echo mode:-85dB
- Surround mode:-90dB
Low distortion rate
- Echo mode: 1%
- Surround mode: 0.2%
·
·
·
Built-in 20Kb SRAM
Automatic reset function
Package type: 16-pin DIP/SOP
·
·
Video disc player
Sound equipments
Applications
·
·
Television
Karaoke systems
General Description
Its built-in 20Kb SRAM can generate delay
time effect and can control the delay time value
through the external VCO resistor.
The HT8970 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, 20Kb SRAM, A/D and D/A
converters as well as delay time control logic.
The VCO circuit can reduce external components and make it easy to adjust the delay time.
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March 14, 2000
HT8970
Block Diagram
L P F 1 _ IN
L P F 1 _ O U T
L P F 2 _ O U T
L P F 2 _ IN
O P 2 _ O U T
4 .7 k W
C O M P
O P 2 _ IN
O P 1 _ IN
4 .7 k W
O P 1 _ O U T
C C 0
C C 1
M O D
D E M
L P F 2
L P F 1
1 /2 V C C
A U T O
R E S E T
R E F
V C C
D O 0
D I
M O
A G N D
M I
2 0 K B its
R A M
D G N D
D O 1
C L O C K
V C O
O S C _ O
v c o
Pin Assignment
V C C
1
1 6
L P F 1 _ IN
R E F
2
1 5
L P F 1 _ O U T
A G N D
3
1 4
L P F 2 _ O U T
D G N D
4
1 3
L P F 2 _ IN
O S C _ O
5
1 2
O P 2 _ O U T
V C O
6
1 1
O P 2 _ IN
C C 1
7
1 0
O P 1 _ IN
C C 0
8
9
O P 1 _ O U T
H T 8 9 7 0
1 6 D IP /S O P
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March 14, 2000
HT8970
Pad Assignment
R E F
V C C
L P F 1 _ IN
L P F 1 _ O U T
L P F 2 _ O U T
L P F 2 _ IN
A G N D
D G N D
1 5
1 4
1 3
1 2
1 1
1 0
1 6
1
(0 ,0 )
2
O S C _ O
5
6
7
8
9
O P 2 _ IN
O P 2 _ O U T
4
O P 1 _ IN
C C 1
O P 1 _ O U T
3
C C 0
V C O
2
Chip size: 1790 ´ 2215 (mm)
* The IC substrate should be connected to VSS in the PCB layout artwork.
Pad Coordinates
Unit: mm
Pad No.
X
Y
Pad No.
X
Y
1
-698.00
701.70
9
652.85
-945.30
2
-669.25
-614.45
10
720.20
882.55
3
-669.25
-762.85
11
571.80
882.55
4
-669.25
-945.30
12
423.40
882.55
5
-405.55
-945.30
13
275.00
882.55
6
-140.05
-945.30
14
-77.60
877.60
7
123.65
-945.30
15
-306.55
849.95
8
389.15
-945.30
16
-560.95
737.70
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March 14, 2000
HT8970
Pad Description
Pad No.
Pad Name
I/O
Internal
Connection
Description
1
DGND
I
¾
Digital ground
2
OSC_O
O
¾
System oscillator output
3
VCO
I
¾
System oscillator input, system frequency
adjustable pin
4
CC1
¾
¾
Current control 1
5
CC0
¾
¾
Current control 0
6
OP1_OUT
O
¾
OP1 output
7
OP1_IN
I
¾
OP1 input
8
OP2_IN
I
¾
OP2 input
9
OP2_OUT
O
¾
OP2 output
10
LPF2_IN
I
¾
Low pass filter 2 input
11
LPF2_OUT
O
¾
Low pass filter 2 output
12
LPF1_OUT
O
¾
Low pass filter 1 output
13
LPF1_IN
I
¾
Low pass filter 1 input
14
VCC
I
¾
Analog and positive power supply
15
REF
I
¾
Analog reference voltage
16
AGND
I
¾
Analog ground
Absolute Maximum Ratings
Supply Voltage.................................-0.3V to 6V
Storage Temperature.................-50°C to 125°C
Input Voltage .................VSS-0.3V to VDD+0.3V
Operating Temperature ..............-20°C to 70°C
Note: These are stress ratings only. Stresses exceeding the range specified under ²Absolute Maximum Ratings² may cause substantial damage to the device. Functional operation of this device
at other conditions beyond those listed in the specification is not implied and prolonged exposure to extreme conditions may affect device reliability.
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March 14, 2000
HT8970
Electrical Characteristics
Symbol
Ta=25°C
Test Conditions
Parameter
VDD
Conditions
Min.
Typ.
Max.
Unit
VCC
Operating Voltage
¾
¾
4.5
5.0
5.5
V
ICC
Operating Current
5V
¾
¾
15
30
mA
GV
Voltage Gain
5V
RL=47kW
¾
-0.9
2.5
dB
VOMAX
Maximum Output Voltage
5V
THD=10%
0.9
1.8
¾
Vrms
THD
Total Harmonic Distortion
5V
30kHz L.P.F.
¾
0.7
1.5
%
NO
Output Noise Voltage
5V
DIN Audio
¾
-85
-60
dBV
PSRR
Power Supply Rejection
Ratio
5V
DVCC=-20dBV
(0.1Vrms)
f=100Hz
¾
-40
-30
dB
Functional Description
· Echo mode
The HT8970 is an echo/surround effect generator with built-in 20Kb SRAM. It ensures low
distortion as well as low noise for processing
audio signal delay. The chip provides two playing modes (echo and surround) and the playing
function block diagrams are shown as follows.
V
V
IN
L P F 1
A /D
O U T
D e la y
D /A
L P F 2
· Surround mode
V
IN
L P F 1
A /D
D e la y
D /A
L P F 2
V
O U T
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March 14, 2000
HT8970
ROSC-fOSC-Delay_time-Distortion Cross table
ROSC
49.8
38.3
31.9
26.77
23.3
20.54
18.08
kW
fOSC
2M
2.5M
3M
3.5M
4M
4.5nm
5M
MHz
Td
327.6
262
218.4
187.2
163.8
145.6
131
ms
THD
1.6
1.3
1.0
0.72
0.7
0.64
0.5
%
ROSC
16.07
14.29
12.98
11.97
11
9.99
9.22
kW
fOSC
5.5M
6M
6.5M
7M
7.5M
8M
8.5M
MHz
Td
119.1
109.2
100.8
93.6
87.36
81.89
77.08
ms
THD
0.47
0.38
0.36
0.35
0.3
0.29
0.28
%
ROSC
8.5
7.54
6.66
6.12
5.5
4.85
4.4
kW
fOSC
9M
10M
11M
12M
13M
14M
15M
MHz
Td
72.79
65.52
59.56
54.59
50.39
46.79
43.68
ms
THD
0.25
0.245
0.23
0.22
0.19
0.185
0.165
%
ROSC
3.98
3.64
3.26
2.92
2.69
2.48
2.28
kW
fOSC
16M
17M
18M
19M
20M
21M
22M
MHz
Td
40.94
38.54
36.39
34.48
32.75
31.19
29.78
ms
THD
0.165
0.15
0.14
0.14
0.13
0.12
0.11
%
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March 14, 2000
HT8970
Application Circuits
Echo mode
0 .6 8 m F
1 m F
1 k W
9 V
1 k W
3
M IC
2
8
4 .7 k W
4 .7 k W
4 7 k W
1 0 0 m F
4 .7 k W
9 V
1
5 V
0 .1 m F
V C C
2
1 0 0 m F
3
4 .7 m F
4
2 0 k W
3 9 p F
5 6 0 0 p F
1 5
O S C _ O
6
V C O
8
1 0 k W
4 .7 m F
1 5 k W
1 0 0 k W
4 .7 m F
5 6 0 p F
4 .7 k W
1 2 k W
1 3 k W
5
R
0 .1 m F
1 6
D G N D
7
0 .1 m F
2 2 m F
L P F 1 _ O U T
A G N D
2 0 k W
4 7 k W
L P F 1 _ IN
R E F
4
5 6 0 W
4 .7 k W
4 .7 m F
1
4 5 5 8
1 0 m F
1 0 m F
O u tp u t
1 5 k W
0 .0 3 3 m F
L P F 2 _ O U T
1 4
L P F 2 _ IN
1 3
O P 2 _ O U T
1 2
C C 1
O P 2 _ IN
C C 0
O P 1 _ IN
1 5 k W
5 6 0 p F
5 6 0 p F
1 0 k W
1 5 k W
1 1
0 .0 4 7 m F
1 0
9
O P 1 _ O U T
0 .0 4 7 m F
H T 8 9 7 0
Note:
: Analog ground,
: Digital ground
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March 14, 2000
HT8970
Surround mode
0 .6 8 m F
1 m F
1 k W
9 V
1 k W
3
M IC
2
8
4 .7 k W
4 .7 k W
4 7 k W
1 0 0 m F
4 .7 k W
9 V
4
2 0 k W
5 6 0 W
4 7 k W
2 2 m F
3 9 p F
5 6 0 0 p F
4 .7 k W
4 .7 m F
1
4 5 5 8
1 5 k W
4 .7 m F
1 0 0 k W
1
5 V
0 .1 m F
V C C
2
1 0 0 m F
3
4 .7 m F
5 6 0 p F
A G N D
4
2 0 k W
1 6
L P F 1 _ IN
R E F
1 5
L P F 1 _ O U T
D G N D
5
O S C _ O
6
V C O
R
1 2 k W
8
0 .1 m F
0 .1 m F
L P F 2 _ IN
1 3
O P 2 _ O U T
1 2
C C 1
O P 2 _ IN
C C 0
O P 1 _ IN
O P 1 _ O U T
1 0 m F
1 4
L P F 2 _ O U T
7
1 0 k W
5 6 0 p F
1 0 k W
3 k W
O u tp u t
1 5 k W
5 6 0 p F
1 5 k W
1 1
0 .0 4 7 m F
9
1 0
0 .0 4 7 m F
H T 8 9 7 0
Note:
: Analog ground,
: Digital ground
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March 14, 2000
HT8970
Holtek Semiconductor Inc. (Headquarters)
No.3 Creation Rd. II, Science-based Industrial Park, Hsinchu, Taiwan, R.O.C.
Tel: 886-3-563-1999
Fax: 886-3-563-1189
Holtek Semiconductor Inc. (Taipei Office)
5F, No.576, Sec.7 Chung Hsiao E. Rd., Taipei, Taiwan, R.O.C.
Tel: 886-2-2782-9635
Fax: 886-2-2782-9636
Fax: 886-2-2782-7128 (International sales hotline)
Holtek Semiconductor (Hong Kong) Ltd.
RM.711, Tower 2, Cheung Sha Wan Plaza, 833 Cheung Sha Wan Rd., Kowloon, Hong Kong
Tel: 852-2-745-8288
Fax: 852-2-742-8657
Copyright Ó 2000 by HOLTEK SEMICONDUCTOR INC.
The information appearing in this Data Sheet is believed to be accurate at the time of publication. However, Holtek
assumes no responsibility arising from the use of the specifications described. The applications mentioned herein are
used solely for the purpose of illustration and Holtek makes no warranty or representation that such applications
will be suitable without further modification, nor recommends the use of its products for application that may present a risk to human life due to malfunction or otherwise. Holtek reserves the right to alter its products without prior
notification. For the most up-to-date information, please visit our web site at http://www.holtek.com.tw.
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March 14, 2000