HOLTEK HT818D0

HT818D0
22.4-Second LOG-PCM Speech
Features
·
·
·
·
·
·
·
·
·
Operating voltage: 3.6V~5.0V
Directly drives an external transistor
Low standby current (1mA typ. for VDD=3V)
Minimal external components
508 words table ROM for key functions
Programmable silence length and end-pulse
width (minimal end-pulse width is 330ms at a
6kHz sampling rate)
22.4-second voice capacity (based on a 6kHz
sampling rate)
Section options
- Retriggerable
- Non-retriggerable
FLAG1 options
- End-pulse output
- 3HzB flash
- 6HzB flash
- Voice output indication
- Busy output
·
FLAG2 options
- 3Hz flash
- 6Hz flash
- Busy output
Controllable volume
12 keys
Key options
- Stop key: KEY12
- Random (only for KEY1)
- Sequential (only for KEY1)
- Repeat (for all KEYs)
- Key debounce time (for all KEYs): 700ms,
22ms, 45ms, 180ms (based on a 6kHz
sampling rate)
- One shot (for all KEYs)
- Level-trigger
- Pull-high resistance (for all KEYs)
Dice form or 20/24-pin DIP/SOP package
·
·
Alert and warning system
Sound effect generators
·
·
·
·
Applications
·
·
·
Leisure products
Alarm clocks
Public address system
General Description
The HT818D0 is a single chip LOG-PCM voice
synthesizer LSI with 22.4-second voice capacity
at a 6kHz sampling rate. The chip when triggered drives a speaker through an external
transistor with a current switch D/A converter
output. Negligible current will be consumed in
the standby state.
The customer¢s voice sources are recorded section by section into an internal mask ROM. The
sectional playback arrangement instructions of
each key are stored in the table ROM. The key
features are also programmable. With such a
flexible structure, the HT818D0 is excellent for
versatile voice applications.
The HT818D0 provides 12 key inputs and 2 programmable FLAG outputs. With a 3.6V~5.0V
power supply, a complete synthesized voice
playback system can be easily built with very
few external components.
1
March 15, 2000
HT818D0
Block Diagram
K E Y 1
K E Y 1 2
O S C 1
O S C 2
A U D
D e b o u n c e
C ir c u it
O n e -s h o t
K e y T a b le
O s c illa to r
C ir c u it
T im e B a s e
G e n e ra to r
T a b le R O M
5 0 8 ´ 1 4 - b it
D A C &
O u tp u t
C o n tro l
V o ic e R O M
1 2 8 K ´ 6 - b it
R O M A d d re s s
C o u n te r
V D D
V S S
S ta tu s
D is p la y
C o n tr o lle r
F L A G 1
F L A G 2
Pin Assignment
K E Y 7
1
2 4
K E Y 6
K E Y 8
2
2 3
K E Y 5
K E Y 7
1
2 0
K E Y 6
K E Y 9
3
2 2
K E Y 4
K E Y 8
2
1 9
K E Y 5
K E Y 1 0
4
2 1
K E Y 3
K E Y 9
3
1 8
K E Y 4
K E Y 1 1
5
2 0
K E Y 2
K E Y 1 0
4
1 7
K E Y 3
K E Y 1 2
6
1 9
K E Y 1
K E Y 1 1
5
1 6
K E Y 2
N C
7
1 8
N C
K E Y 1 2
6
1 5
K E Y 1
V D D
8
1 7
N C
N C
7
1 4
F L A G 2
A U D
9
1 6
N C
V D D
8
1 3
V S S
O S C 2
1 0
1 5
N C
A U D
9
1 2
F L A G 1
O S C 1
1 1
1 4
F L A G 2
O S C 2
1 0
1 1
O S C 1
F L A G 1
1 2
1 3
V S S
H T 8 1 8 D 0
2 0 D IP /S O P
H T 8 1 8 D 0
2 4 D IP /S O P
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March 15, 2000
HT818D0
Pad Assignment
K E Y 5
K E Y 1 2
K E Y 6
2
K E Y 7
K E Y 1 1
K E Y 8
1
K E Y 9
K E Y 1 0
Pad Coordinates
1 9
1 8
1 7
1 6
1 5
3
1 4
K E Y 4
1 3
K E Y 3
1 2
K E Y 2
1 1
K E Y 1
(0 ,0 )
7
O S C 1
8
9
1 0
Pad No.
X
Y
1
-914.50
1997.95
2
-914.50
1854.55
3
-914.50
1663.95
4
-987.90
-2023.45
5
-254.60
-1996.95
6
-18.90
411.90
-1996.95
7
8
674.70
-1996.95
9
806.10
-2027.55
10
11
12
13
14
15
16
17
18
937.90
912.80
912.80
912.80
912.80
709.50
179.20
22.00
-156.40
-1996.95
1501.15
1639.75
1835.15
1978.75
1949.25
1949.25
1949.25
1949.25
19
-734.20
1949.25
-1996.95
F L A G 2
V S S
F L A G 1
6
O S C 2
V D D
5
A U D
4
Unit: mm
Chip size: 2270 ´ 4400 (mm)2
* The IC substrate should be connected to VSS in the PCB layout artwork.
Pad Description
Pad Name
I/O
Internal
Connection
Description
1~3
KEY10~KEY12
I
Pull-high
Trigger key, low active. Key features such as
debounce time, pull-high resistance and repeat
are all by mask option.
4
VDD
¾
¾
5
AUD
O
PMOS
Open Drain
6
OSC2
O
¾
Oscillator output pin
7
OSC1
I
¾
Oscillator input pin
Pad No.
Positive power supply
Voice output for driving an external transistor
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March 15, 2000
HT818D0
Pad No.
Pad Name
I/O
Internal
Connection
Description
3HzB/6HzB flash output, busy output,
end-pulse or voice output indication (by mask
option). Open drain, active low output.
8
FLAG1
O
NMOS
Open Drain
9
VSS
¾
¾
10
FLAG2
O
NMOS
Open Drain
3Hz/6Hz flash output or busy output (by mask
option). Open drain, active low output.
11~19
KEY1~KEY9
I
Pull-high
Trigger key, low active. Key features such as
debounce time, pull-high resistance and repeat
are all by mask option.
Negative power supply, 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.
Electrical Characteristics
Symbol
Parameter
Ta=25°C
Test Conditions
VDD
Conditions
Min.
Typ.
Max.
Unit
VDD
Operating Voltage
¾
¾
3.6
¾
5.0
V
IDD
Operating Current
3V
No load
¾
200
400
mA
ISTB
Standby Current
3V
¾
¾
1
3
mA
IO
Max. AUD Output Current
3V
VOH=0.6V
-1.5
-2
¾
mA
IOL
FLAG Sink Current
3V
VOL=0.3V
1.5
3.0
¾
mA
VIH
²H² Input Voltage
¾
¾
0.8VDD
¾
VDD
V
VIL
²L² Input Voltage
¾
¾
0
¾
0.2VDD
V
fOSC
Oscillating Frequency
3V
ROSC=530kW
76
96
116
kHz
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March 15, 2000
HT818D0
Functional Description
The HT818D0 is a mask ROM type voice synthesizer with 22.4-second voice capacity. A group of
pre-recorded voice sections is played upon receipt
of key trigger input signals. Two FLAG signals
are output while playing voices.
The oscillator is turned on when triggered by a
key input. After playing, it is immediately turned
off and the chip goes into the standby state.
The 22.4-second voice capacity can be divided
into sections of arbitrary length. Notice that the
silence length and end-pulse width are not included in the memory.
The voice ROM is originally designed to continuously record the 22.4-second voice data at a 6kHz
sampling rate. A higher sampling rate can generate voices of better playback quality, but will
shorten the total recording time. On the other
hand, a lower sampling rate results in longer recording time but sacrifice voice quality.
Voice ROM
By using Holtek¢s programming tools, the contents and arrangement of sections, as well as
key features and FLAG output are all programmable before device fabrication.
The playback time can be significantly extended
by making use of coding efficiency, silence playing, section repeating, section cascade, etc.
The IC provides 12 key inputs (KEY1~KEY12).
Of the 12 keys, KEY1 can be optioned as a direct, sequential or random trigger key. KEY12
can be selected as a stop or direct key. The remaining 10 keys (KEY2~KEY11) are used as direct keys exclusively.
Section
Section is the basic element constituting the
contents of voice ROM. During programming,
the customer¢s voice sources can be divided into
as many sections as required. A section can be
composed of a voice or an interval of silence.
However, the silence length is not counted in
the voice ROM. The total number of sections included should be less than 508 due to the space
limitation of the function table ROM. The total
length of the included sections is limited by the
voice ROM.
Play function block diagram
V
K e y
tr ig g e r
K
fu n
ta
R
K e y
fe a tu re s
o p tio n
e y
c tio n
b le
O M
V o ic e
R O M
D D
D /A
A section, when triggered by a key input, can be
played once, repeatedly or cascaded with other
sections, depending on the key function table
instructions.
F la g
o u tp u t
P la y in g c o n tr o l lo g ic
System oscillator
The following are examples of section division:
The HT818D0 has a built-in RC oscillator
which requires only one external resistor for
normal applications. The oscillator frequency
is typically 96kHz for an external resistor of
530kW. The required oscillator frequency may
vary with different sampling rates in the process of voice programming. As a result, the
value of the oscillator resistor may be different for different items.
E x a m p le 1 : O n e s e c tio n o n ly
s e c .1
R O M
E x a m p le 2 : 3 s e c tio n d iv is io n
s e c .1
E x a m p le 3 : N
s e c .1
R
s e c .3
R O M
O S C 1
H T 8 1 8 D 0
s e c .2
s e c tio n d iv is io n
s e c .2
s e c .N
R O M
O S C
O S C 2
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March 15, 2000
HT818D0
The following is an example of the function table:
In addition, a section can be set as retriggerable
or non-retriggerable depending on the code option.
· Retriggerable
When the currently playing section is set as
retriggerable, it will be stopped immediately
upon receipt of other key inputs.
· Non-retriggerable
Group 1
sec.1 + sec.2 + sec.3 + sec.5
Group 2
sec.3
Group 3
sec.2 + sec.2 + sec.3 + sec.4
Group 4
sec.5 + sec.3
As illustrated in the above table, the voice
ROM is composed of 5 sections and the function table of 11 sections. If KEY1 is momentarily triggered, section 1, section 2, section 3
and section 5 are played in sequence and then
stops. Triggering KEY2 plays section 3, and
so on.
When the currently playing section is selected
as non-retriggerable, it will go on playing till
the whole section is completed, whether or not
there is a key input in the process of playing.
For a key group, some sections can be set as
retriggerable and some as non-retriggerable.
When a retriggerable section of a key group is
playing, any key can be input to interrupt its
p l a y i ng . O n the ot her ha n d , i f a
non-retriggerable section is playing, any key
interrupt is ignored.
· KEY1 as a sequential or random key
When KEY1 is optioned as a sequential or random key, it can include multiple groups
(sub-groups) in the function table. However,
the remaining 11 keys (KEY2~KEY12) are used
as direct keys exclusively and comprise only
one group in the function table.
Group
The HT818D0 plays according to the basis of
the key input. A group can be made up of one or
more sections. When a key is triggered, the corresponding group is played immediately. For
example, triggering KEY2 plays group 2, and so
on. The same section is allowed to appear in different groups. However, KEY1 can be made up
of multiple groups when it is optioned as a sequential or random key. Otherwise, each key is
composed of one group only.
An example is shown below:
Group 1-1 sec.4 + sec.2
Group 1-2 sec.1 + sec.3
:
:
:
:
Group 1-N sec.2 + sec.3
Key function table
The sections included in the voice ROM are
played according to the instructions of the key
function table. The function table contains
group information and the playing order of sections in the groups. Notice that the total number of sections included in the groups should be
less than 508 the space limitation of the function table ROM.
Group 2
sec.2 + sec.3
Group 3
sec.3 + sec.5
Group 4
sec.1 + sec.5 + sec.2
As indicated in the above table, KEY1 can be
made up of sub-groups. Each time KEY1 is
triggered, the corresponding sub-groups are
played in sequence.
The playing sequence of sequential KEY1 is:
Group 1-1 ® Group 1-2 ® Group 1-3 ..... ®
Group 1-N (the last group) ®Group 1-1 .....
¨ The playing sequence of random KEY1 is:
Group 1-3 ® Group 1-5 ..... ® Group 1-N ®
Group 1-3 ® Group 1-5 .....
¨
· KEY1 as a direct key
Each key is mapped to a group in the
function table. If a key is not used, the group
mapped to that key is a piece of silence.
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March 15, 2000
HT818D0
For instance, if sub-group 1-3 is the previous
playing group, sub-group 1-5 will start playing
after 2 pulses are applied to KEY1, and so on.
That KEY1 functions as a random key is a
special case of sequential key, which combines a particular arrangement of sub-group
playing sequence.
¨
¨
To make easy selection of KEY1 sub-groups,
one of KEY2~KEY12 should be programmed
as silence. Then this silence key has to be
triggered to reset KEY1. By so doing, the
playing sub-group of KEY1 is directly specified by the pulse number applied to KEY1
(see Figure 2).
Reset of KEY1 playing sequence
If a sub-group of KEY1 group is being played
and one of KEY2~KEY12 is triggered, the
playing sub-group will be terminated, and
the newly triggered key group is played instead. The first sub-group will start playing
when KEY1 is retriggered. In other words,
the KEY1 playing sequence is reset whenever a key other than KEY1 is triggered (see
Figure 1).
· KEY12 as a stop key (by mask option)
When KEY12 functions as a stop key, any
voice output can be stopped by pressing
KEY12.
Sub-group selection
When KEY1 is triggered with pulses, a desired sub-group can be selected by controlling
its corresponding pulse number. However,
the features of KEY1 have to be set in the following ways:
-
· KEY1~KEY11 as a repeat key
KEY1~KEY11 all function as repeat key if
one of the eleven keys is set as a repeat key.
In other words, once the mode of one of
KEY1~KEY11 is determined, the remaining
10 keys are set accordingly.
sequential or random
retriggerable
minimum key debounce time
(@700ms, fOSC=96kHz)
As a repeat key, the sections included can be
played sequentially or repeatedly till other
key input is triggered. KEY12 has no other
choice but functions as a stop key when
KEY1~KEY11 are set as repeat keys.
K E Y 1
K E Y 2 ~ K E Y 1 2
A U D
G ro u p 1 -1
G ro u p 1 -2
G ro u p 1 -N
G ro u p (2 ~ 1 2 )
G ro u p 1 -1
Figure1 Reset of KEY1 playing sequence
K E Y 1
K E Y 2 ~ K E Y 1 2
( S ile n c e )
N p u ls e
M
p u ls e
A U D
G ro u p 1 -N
G ro u p 1 -M
Figure 2 KEY1 sub-group selection
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March 15, 2000
HT818D0
Key features
* Level hold
When one of the 12 keys is pressed and held
down, the group corresponding to that held
key will play until the pressed key is released, then the group will immediately
stop regardless of the rest.
· Key priority
When two or more keys are triggered simultaneously, the output voice is determined by the
key priority as shown below:
KEY1>KEY2>......KEY11>KEY12
K E Y N
· Key debounce time
There are four kinds of key-in debounce time
that can be selected by mask option, namely
700ms, 22ms, 45ms and 180ms. The key
debounce time varies with the value of system
frequency.
A U D
G ro u p N
When voices are playing, both FLAG1 and
FLAG2 pins are activated to output one of the
following signals through code option.
Four kinds of key input pin pull-high resistance can be selected by mask option,
namely, 20kW, 50kW, 100kW and 200kW.
The resistance may vary with VDD, temperatures and the chip itself due to process
variations.
FLAG1 can be optioned as one of the following
signal outputs:
None, 3HzB flash, Busy, 6HzB flash, Voice indicator, or End-pulse output
· Trigger mode
FLAG2, on the other hand, can be set as one of
the following signal outputs:
All of the 12 keys can be optioned as one-shot
trigger mode, level hold mode or level-trigger
mode.
None, 3Hz flash, 6Hz flash, or Busy output
· 3Hz/3HzB flash
One shot
When one of the 12 keys (KEY1~KEY12) is
pressed momentarily or held down, the
group corresponding to that key will play
once.
When voices are playing, the FLAG1 as well
as FLAG2 pin outputs a 3Hz signal to drive
an LED. The signal is active low, 25% duty.
Once the voice output is terminated, the
FLAG1 and FLAG2 pins become floating outputs. When the FLAG1 and the FLAG2 pins
are optioned as 3HzB and 3Hz outputs, they
will be alternately output at a 3Hz rate.
K E Y N
A U D
G ro u p N
G ro u p N
FLAG
· Pull-high resistance
¨
G ro u p N
G ro u p N
A U D
¨
Level trigger
When one of the 12 keys is pressed and held
down, the corresponding group will keep
playing. Once the pressed key is released,
the group will not stop till the included sections are all completed.
F L A G
: F lo a tin g
K E Y N
A U D
G ro u p N
G ro u p N
G ro u p N
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March 15, 2000
HT818D0
· 6Hz/6HzB flash
¨
When voices are playing, the FLAG1 pin
outputs a 6Hz signal to drive an LED. The
signal is active low, 25% duty. Once the voice
output is terminated, the FLAG1 pin becomes a floating output. When the FLAG1
and the FLAG2 pins are optioned as 6HzB
and 6Hz outputs, they will be alternately
output at a 6Hz rate.
End-pulse output
When the voice output is completed, the
FLAG1 pin outputs an active low pulse. The
pulse width can be programmed depending
on the customer¢s requirements.
The FLAG1 as well as FLAG2 pins are both
floating outputs when the chip is in the
standby state.
A U D
A U D
F L A G
F L A G
: F lo a tin g
: F lo a tin g
Volume control
· Busy output
The function of volume control can be set by
mask option. A code is written in the function
table for the purpose of controlling the volume
of each section output after the volume control
function is chosen. There are two volume options, namely, full range and half range.
When a voice group is playing, the outputs of
both FLAG1 and FLAG2 are turned low, indicating that the chip is busy.
A U D
F L A G
AUD
The AUD pin is a PMOS open drain structure.
It outputs voice signals to drive a speaker
through an external NPN transistor when the
chip is active. The AUD pin becomes a floating
output when the chip is in the standby state.
: F lo a tin g
In addition to the above-stated output signals, FLAG1 can also generate one of the following signals by code option:
¨
The 8050 type transistor with hFE@150 is recommended for an output driver.
Voice indicator output
FLAG1 is active low when voices are playing. FLAG1 is also turned low when a voice
section is output. The brightness of FLAG1
varies with the volume. FLAG1 becomes a
floating output after the silence section is
output or the voice output is terminated.
V
O S C 1
R
D D
V D D
S P K
O S C
O S C 2
A U D
8 0 5 0
V S S
H T 8 1 8 D 0
A U D
F L A G
: F lo a tin g
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March 15, 2000
HT818D0
Application Circuits
General application
K E Y 5
K E Y 6
K E Y 7
K E Y 8
K E Y 9
K E Y 1 0
1
K E Y 1 1
K E Y 4
1 4
2
1 9
K E Y 1 2
1 8
1 7
1 6
K E Y 3
1 5 1 3
K E Y 2
1 2
3
K E Y 1
1 1
H T 8 1 8 D 0
V
D D
8
1 0
9
V S S
F L A G 2
A U D
8 0 5 0
7
O S C 1
6
4
V D D
F L A G 1
5
O S C 2
S P K
8 W
R o s c
R
R
* T h e IC
s u b s tr a te s h o u ld b e c o n n e c te d to V S S in th e P C B la y o u t a r tw o r k .
V
1 9
K E Y 1
K E Y 2
K E Y 3
2 0
2 1
2 2
K E Y 4
2 3
2 4
1
2
3
4
5
6
1 1
V D D
F L A G 1
F L A G 2
K E Y 5
A U D
K E Y 6
N C
K E Y 7
N C
K E Y 8
N C
K E Y 9
N C
K E Y 1 0
N C
K E Y 1 1
V S S
K E Y 1 2
O S C 1
O S C 2
8
1 2
R
R
S P K
8 W
1 4
9
D D
8 0 5 0
7
1 5
1 6
1 7
1 8
1 3
1 0
H T 8 1 8 D 0
R = 1 0 0 W ~ 3 3 0 W
R o s c
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March 15, 2000
HT818D0
Parallel application
V
1 0 0 W ~
3 3 0 W
1 0 0 W ~
3 3 0 W
F L A G 1
R
F L A G 2 V D D
O S C 2
1 0 0 W ~
3 3 0 W
F L A G 1
O S C 1
R
F L A G 2 V D D
A U D
H T 8 1 8 D 0
V S S
1 0 0 W ~
3 3 0 W
O S C
K E Y 1
O S C
O S C 2
O S C 1
V S S
8 0 5 0
A U D
H T 8 1 8 D 0
K E Y 1 2
D D
K E Y 1 2
K E Y 1
Cascade or external driving
V
R
O S C 2
tr ig g e r
o u t
O S C
O S C 1
F L A G 1
K E Y 1
K E Y 1 2
O S C
O S C 2
O S C 1
H T 8 1 8 D 0
A U D
F L A G 1
A U D
H T 8 1 8 D 0
V S S
K E Y
R
D D
8 0 5 0
V S S
Power-on play (one shot)
V
D D
S W
R
O S C 2
O S C
1 0 0 W ~
3 3 0 W
O S C 1
1 0 0 W ~
3 3 0 W
F L A G 1
F L A G 2
H T 8 1 8 D 0
K E Y
0 .1 m F
V D D
A U D
8 0 5 0
V S S
1 .2 M W
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March 15, 2000
HT818D0
Power-on play (continuous)
V
D D
S W
R
1 0 0 W ~
3 3 0 W
O S C
O S C 2
1 0 0 W ~
3 3 0 W
F L A G 1
O S C 1
F L A G 2
H T 8 1 8 D 0
K E Y
V D D
A U D
8 0 5 0
V S S
With volume adjustment
V
D D
S W
R
O S C 2
O S C
1 0 0 W ~
3 3 0 W
O S C 1
1 0 0 W ~
3 3 0 W
F L A G 1
F L A G 2
H T 8 1 8 D 0
K E Y 1
K E Y 1 2
V D D
A U D
8 0 5 0
V S S
1 k W
1 0 m F
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March 15, 2000
HT818D0
Push-pull output
To prevent the speaker and driver transistor from damage due to excess power dissipation which results from a high voltage power supply (4.5V~5.5V), the following push-pull output stage is recommended.
V
D D
S W
R
O S C 2
O S C
1 0 0 W ~
3 3 0 W
1 0 0 W ~
3 3 0 W
F L A G 1
O S C 1
F L A G 2
V D D
H T 8 1 8 D 0
K E Y 1
V S S
K E Y 1 2
1 N 4 1 4 8
A U D
8 0 5 0
8 5 5 0
4 7 m F
4 3 0 W
Coupling to power amplifier
V
R
O S C 2
O S C
1 0 0 W ~
3 3 0 W
O S C 1
1 0 0 W ~
3 3 0 W
F L A G 1
F L A G 2
H T 8 1 8 D 0
K E Y 1
D D
K E Y 1 2
V D D
A U D
0 .1 m F
V S S
5 6 0 W
1 0 k W
13
T o
p o w e r
a m p
March 15, 2000
HT818D0
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.
14
March 15, 2000