HOLTEK HT817D0

HT817D0
16.8-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)
16.8-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
12 keys
Controllable volume
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 of)
- 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 HT817D0 is a single chip LOG-PCM voice
synthesizer LSI with 16.8-second voice capacity
at 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 HT817D0 is excellent for
versatile voice applications.
The HT817D0 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
HT817D0
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
9 6 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 7 D 0
2 0 D IP /S O P
H T 8 1 7 D 0
2 4 D IP /S O P
2
March 15, 2000
HT817D0
Pad Assignment
K E Y 6
K E Y 5
K E Y 1 2
K E Y 7
2
K E Y 8
1
K E Y 1 1
K E Y 9
K E Y 1 0
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 )
8
O S C 1
F L A G 1
9
1 0
F L A G 2
7
V S S
6
O S C 2
V D D
5
A U D
4
2
Chip size: 2270 ´ 3630 (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
2
3
4
5
6
7
8
9
10
-914.50
-914.50
-914.50
-987.90
-254.60
-18.90
411.90
674.70
806.10
937.90
1612.75
1469.35
1278.75
-1638.25
-1611.75
-1611.75
-1611.75
-1611.75
-1642.35
-1611.75
11
12
13
14
15
16
17
18
19
912.80
912.80
912.80
912.80
709.50
179.20
22.00
-156.40
-734.20
1115.95
1254.55
1449.95
1593.55
1564.05
1564.05
1564.05
1564.05
1564.05
3
March 15, 2000
HT817D0
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
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, active low. Key features such as
debounce time, pull-high resistance and repeat
are all by mask option.
Pad No.
Positive power supply
Voice output for driving an external transistor
3HzB/6HzB flash output, busy output,
end-pulse or voice output indication (by mask
option). Open drain, active low output.
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.
4
March 15, 2000
HT817D0
Electrical Characteristics
Symbol
Parameter
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
Functional Description
Play function block diagram
The HT817D0 is a mask ROM type voice synthesizer with 16.8-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.
V
K e y
tr ig g e r
The 16.8-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.
K e y
fe a tu re s
o p tio n
K
fu n
ta
R
e y
c tio n
b le
O M
V o ic e
R O M
D /A
F la g
o u tp u t
P la y in g c o n tr o l lo g ic
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.
D D
System oscillator
The HT817D0 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.
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. As for the
remaining 10 keys (KEY2~KEY11), they are
used as direct keys exclusively.
O S C 1
H T 8 1 7 D 0
R
O S C
O S C 2
5
March 15, 2000
HT817D0
In addition, a section can be set as retriggerable
or non-retriggerable depending on the code option.
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.
· Retriggerable
Voice ROM
When the currently playing section is set as
retriggerable, it will stop immediately upon
receipt of other key inputs.
The voice ROM is originally designed to continuously record the 16.8-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.
· Non-retriggerable
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.
The playback time can be significantly extended
by making use of coding efficiency, silence playing, section repeating, section cascade, etc.
Of 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 triggered to interrupt
its playing. On the other hand, if it is a
non-retriggerable section playing, any key interrupt is ignored.
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
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
voice ROM.
Group
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.
The HT817D0 plays groups on 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
comprised by one group only.
The following are examples of section division:
Key function table
E x a m p le 1 : O n e s e c tio n o n ly
The sections include in the voice ROM are
played according to the instructions of the key
function table. The function table contains
group information as well as 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.
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
s e c .2
s e c .3
R O M
E x a m p le 3 : N
s e c .1
s e c tio n d iv is io n
s e c .2
s e c .N
R O M
6
March 15, 2000
HT817D0
· KEY1 as a direct key
An example is shown below:
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.
Group 1-1 sec.4 + sec.2
Group 1-2 sec.1 + sec.3
:
:
The following is an example of the function table:
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
:
:
Group 1-N sec.2 + sec.3
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.
As illustrated in the above table, 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
stopped. Triggering KEY2 plays section 3,
and so forth.
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 .....
That KEY1 functions as a random key is a
special case of sequential key, which combines a particular arrangement of sub-group
playing sequence.
¨
· 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.
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
N p u ls e
M
p u ls e
K E Y 2 ~ K E Y 1 2
( S ile n c e )
A U D
G ro u p 1 -N
G ro u p 1 -M
Figure 2 KEY1 sub-group selection
7
March 15, 2000
HT817D0
¨
¨
Key features
Reset of KEY1 playing sequence
If a sub-group of KEY1is playing and one of
KEY2~KEY12 is triggered, the playing
sub-group will be terminated, and the newly
triggered key group come into play instead.
The first sub-group will start playing by
retriggering KEY1. In other words, the KEY1
playing sequence is reset whenever a key
otherthanKEY1istriggered(seeFigure1).
· 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
· 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 the system frequency.
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:
· Pull-high resistance
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.
sequential or random
- retriggerable
- minimum key debounce time
(@700ms, fOSC=96kHz)
For instance, if sub-group 1-3 is the previous
playing group, sub-group 1-5 will start playing
after 2 pulses are input to KEY1, and so on.
-
· Trigger mode
All of the 12 keys can be optioned as one-shot
trigger mode, level hold mode or level-trigger
mode.
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).
¨
· KEY12 as a stop key (by mask option)
When KEY12 functions as a stop key, any
voice output can be stopped by pressing
KEY12.
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.
K E Y N
A U D
G ro u p N
· 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.
¨
As a repeat key, the sections included can be
played sequentially and 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.
G ro u p N
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.
K E Y N
A U D
G ro u p N
8
G ro u p N
G ro u p N
March 15, 2000
HT817D0
¨
· 6Hz/6HzB flash
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.
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 FLAG1 and
FLAG2 pins are optioned as 6HzB and 6Hz
outputs, they will be alternately output at a
6Hz rate.
K E Y N
A U D
G ro u p N
G ro u p N
G ro u p N
A U D
FLAG
F L A G
When voices are playing, both FLAG1 and
FLAG2 pins are activated to output one of the
following signals through code option.
: F lo a tin g
FLAG1 can be optioned as one of the following
signal outputs:
· Busy output
When a voice group is playing, the outputs of
both FLAG1 and FLAG2 are turned low, indicating that the chip is busy.
None, 3HzB flash, Busy, 6HzB flash, Voice indicator, or End-pulse output
FLAG2, on the other hand, can be set as one of
the following signal outputs:
A U D
None, 3Hz flash, 6Hz flash, or Busy output
F L A G
· 3Hz/3HzB flash
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.
: F lo a tin g
A U D
F L A G
: F lo a tin g
9
March 15, 2000
HT817D0
Volume control
In addition to the above-stated output signals, FLAG1 can also generate one of the following signals by code option:
¨
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.
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
floating after the silence section is output or
the voice output is terminated.
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.
A U D
F L A G
The 8050 type transistor with hFE@150 is recommended for an output driver.
: F lo a tin g
¨
V
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.
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 7 D 0
The FLAG1 as well as FLAG2 pins are both
floating outputs when the chip is in the
standby state.
A U D
F L A G
: F lo a tin g
10
March 15, 2000
HT817D0
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
2 1 9
K E Y 1 2
K E Y 4
1 4
1 8
K E Y 3
1 5 1 3
1 6
1 7
3
K E Y 2
1 2
K E Y 1
1 1
H T 8 1 7 D 0
V
D D
S P K
8 W
6
5
4
V D D
8
7
1 0
V S S
F L A G 2
F L A G 1
O S C 1
O S C 2
A U D
8 0 5 0
9
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
2 0
2 1
V D D
K E Y 2
F L A G 1
K E Y 3
2 2
K E Y 4
2 3
2 4
1
2
3
4
5
6
1 1
K E Y 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 2
O S C 1
H T 8 1 7 D 0
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
R = 1 0 0 W ~ 3 3 0 W
R o s c
11
March 15, 2000
HT817D0
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
F L A G 1
O S C 1
K E Y 1
R
F L A G 2 V D D
A U D
H T 8 1 7 D 0
V S S
1 0 0 W ~
3 3 0 W
1 0 0 W ~
3 3 0 W
O S C
O S C 2
K E Y 1 2
V S S
O S C
O S C 1
8 0 5 0
A U D
H T 8 1 7 D 0
K E Y 1
D D
K E Y 1 2
Cascade or external driving
V
R
O S C 2
tr ig g e r
o u t
O S C
F L A G 1
O S C 1
F L A G 1
A U D
H T 8 1 7 D 0
V S S
K E Y
K E Y 1 2
K E Y 1
R
D D
O S C
O S C 2
O S C 1
H T 8 1 7 D 0
A U 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 7 D 0
8 0 5 0
V S S
K E Y
0 .1 m F
V D D
A U D
1 .2 M W
12
March 15, 2000
HT817D0
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
V D D
A U D
H T 8 1 7 D 0
K E Y
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 7 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
13
March 15, 2000
HT817D0
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
O S C 1
F L A G 1
F L A G 2
V D D
K E Y 1 2
V S S
1 N 4 1 4 8
A U D
H T 8 1 7 D 0
K E Y 1
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
V D D
A U D
H T 8 1 7 D 0
K E Y 1
D D
K E Y 1 2
0 .1 m F
V S S
5 6 0 W
1 0 k W
14
T o
p o w e r
a m p
March 15, 2000
HT817D0
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.
15
March 15, 2000