HOLTEK HT1622

HT16270
RAM Mapping 64 ´16 LCD Controller for I/O mC
Features
·
·
·
·
·
·
·
·
·
Operating voltage: 2.7V~5.2V
External Crystal 32.768kHz oscillator
1/5 bias, 1/16 duty, frame frequency is 64Hz
Max. 64´16 patterns, 16 commons,
64 segments
Built-in internal resistor type bias generator
3-wire serial interface
8 kinds of time base/WDT selection
Time base or WDT overflow output
Built-in LCD display RAM
·
·
·
·
·
·
·
R/W address auto increment
Two selectable buzzer frequencies
(2kHz/4kHz)
Power down command reduces power
consumption
Software configuration feature
Data mode and Command mode instructions
Three data accessing modes
VLCD pin to adjust LCD operating voltage
General Description
configuration feature of the HT16270 make it
suitable for multiple LCD applications including LCD modules and display subsystems. Only
three lines are required for the interface between the host controller and the HT16270.
The HT162X series have many kinds of products that match various applications.
HT16270 is a peripheral device specially designed for I/O type mC used to expand the display capability. The max. display segment of
the device are 1024 patterns (64´16). It also
supports serial interface, buzzer sound, watchdog timer or time base timer functions. The
H T 1 6 2 7 0 i s a m em or y m a p p i n g a n d
multi-function LCD controller. The software
Selection Table
HT162X
HT1620 HT1621 HT1622 HT16220 HT1623 HT1625 HT1626 HT1627 HT16270
COM
4
4
8
8
8
8
16
16
16
SEG
32
32
32
32
48
64
48
64
64
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Built-in Osc.
Crystal Osc.
Ö
1
Ö
April 21, 2000
HT16270
Block Diagram
O S C O
D is p la y R A M
O S C I
C S
C o n tro l
a n d
T im in g
C ir c u it
R D
W R
C O M 0
C O M 1 5
L C D D r iv e r /
B ia s C ir c u it
D A T A
S E G 0
S E G 6 3
V D D
V S S
V L C D
B Z
W a tc h d o g T im e r
a n d
T im e B a s e G e n e r a to r
T o n e F re q u e n c y
G e n e ra to r
B Z
IR Q
Pin Assignment
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
4 4
4 5
4 6
4 7
4 8
4 9
5 0
5 1
5 2
5 3
5 4
5 5
5 6
5 7
5 8
5 9
6 0
6 1
6 2
6 3
C S
R D
W R
D A T A
V S S
O S C I
O S C O
V D D
V L C D
IR Q
B Z
B Z
T 1
T 2
T 3
T 4
C O M 0
C O M 1
C O M 2
C O M 3
C O M 4
C O M 5
C O M 6
C O M 7
C O M 8
C O M 9
C O M 1 0
C O M 1 1
C O M 1 2
N C
1 0 0 9 9 9 8 9 7 9 6 9 5 9 4 9 3 9 2 9 1 9 0 8 9 8 8 8 7 8 6 8 5 8 4 8 3 8 2 8 1
1
8 0
2
7 9
3
7 8
4
7 7
5
7 6
6
7 5
7
7 4
8
7 3
9
7 2
1 0
7 1
1 1
7 0
1 2
6 9
1 3
6 8
1 4
6 7
H T 1 6 2 7 0
1 0 0 Q F P
1 5
1 6
6 6
6 5
1 7
6 4
1 8
6 3
1 9
6 2
2 0
6 1
2 1
6 0
2 2
5 9
2 3
5 8
2 4
5 7
5 6
2 5
2 6
5 5
2 7
5 4
2 8
5 3
2 9
5 2
3 0
3 1 3 2 3 3 3 4 3 5 3 6 3 7 3 8 3 9 4 0 4 1 4 2 4 3 4 4 4 5 4 6 4 7 4 8 4 9 5 0
5 1
S E G
S E G
N C
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
N C
N C
S E G
S E G
4 3
4 2
4 1
4 0
3 9
3 8
3 7
3 6
3 5
3 4
3 3
3 2
3 1
3 0
2 9
2 8
2 7
2 6
2 5
2 4
2 3
2 2
2 1
2 0
1 9
1 8
1 7
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
C O M
C O M
C O M
1 6
1 5
1 4
1 3
1 2
1 1
1 5
1 0
9
8
7
6
5
4
3
2
1
0
1 4
1 3
2
April 21, 2000
HT16270
Pad Assignment
7 9
7 8
7 7
7 6
7 5
7 4
S E G 4 2
8 0
8 1
S E G 4 3
S E G 4 4
8 2
S E G 4 5
S E G 4 6
8 4 8 3
S E G 4 7
S E G 4 8
8 5
S E G 4 9
S E G 5 0
8 6
S E G 5 1
S E G 5 2
8 7
S E G 5 3
S E G 5 4
8 8
8 9
S E G 5 5
S E G 5 6
9 0
9 1
S E G 5 7
S E G 5 8
9 2
S E G 5 9
S E G 6 0
9 3
S E G 6 1
S E G 6 2
C S
R D
9 4
S E G 6 3
W R
S
C I
O
D
D
9 5
7 2
7 3
1
D A T A
V S
O S
O S C
V D
V L C
9 6
2
7 1
S E G 4 1
7 0
S E G 4 0
S E G 3 9
6 9
3
4
6 8
5
6 7
6
6 6
7
IR Q
6 5
8
B Z
6 4
6 3
B Z
9
T 1
1 0
T 2
T 3
1 2
5 9
T 4
C O M 0
1 3
5 8
1 4
5 7
C O M 1
C O M 2
1 5
5 6
1 6
5 5
6 2
6 1
(0 , 0 )
1 1
6 0
5 2
2 0
5 1
C O M 7
2 1
5 0
C O M 8
2 2
4 9
C O M 9
2 3
2 6
3 0
3 1
3 2
3 3
3 4
3 5
3 6
3 7
3 8
3 9
4 0
4 4
4 5
4 6
4 7
S E G 3 6
S E G 3 5
S E G 3 4
S E G 3 3
S E G 3 2
S E G 3 1
S E G 3 0
S E G 2 9
S E G 2 8
S E G 2 7
S E G 2 6
S E G 2 5
S E G 2 4
S E G 2 3
S E G 2 2
S E G 2 1
S E G 2 0
S E G 1 9
4 8
S E G 1 8
4 3
S E G 1 7
Chip size: 245 ´ 237 (mil)
4 1 4 2
S E G 1 6
S E G 1 5
S E G 1 0
S E G 9
S E G 8
S E G 7
2 9
S E G 6
S E G 5
2 7 2 8
S E G 4
S E G 3
2 5
S E G 2
S E G 1
2 4
S E G 1 4
S E G 1 3
1 9
S E G 1 2
S E G 1 1
C O M 5
C O M 6
S E G 0
C O M 1 5
5 3
C O M 1 4
C O M 1 3
5 4
1 8
C O M 1 2
C O M 1 1
1 7
C O M 1 0
C O M 3
C O M 4
S E G 3 8
S E G 3 7
2
* The IC substrate should be connected to VDD in the PCB layout artwork.
3
April 21, 2000
HT16270
Pad Coordinates
Pad No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
X
-116.57
-116.68
-116.72
-116.72
-116.72
-115.93
-116.72
-116.72
-116.72
-115.94
-115.94
-115.94
-115.90
-115.97
-115.93
-115.93
-115.93
-115.93
-115.97
-115.93
-115.93
-115.94
-115.94
-108.08
-96.03
-89.43
-77.43
-70.82
-58.83
-52.17
-40.22
-33.58
-21.58
-14.98
-2.97
3.67
15.63
22.27
34.28
40.88
52.88
59.47
71.47
78.13
90.07
96.72
108.72
116.19
Unit: mil
Y
99.90
90.80
84.15
77.50
70.90
64.25
54.75
41.45
21.85
11.39
-0.60
-7.18
-19.21
-25.85
-37.85
-44.45
-56.45
-63.05
-75.05
-81.70
-93.65
-100.30
-112.37
-112.07
-112.05
-112.05
-112.05
-112.05
-112.05
-112.05
-112.05
-112.05
-112.00
-112.05
-112.00
-112.05
-112.05
-112.05
-112.05
-112.05
-112.05
-112.05
-112.00
-112.00
-112.05
-112.05
-112.00
-111.82
Pad No.
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
4
X
116.15
116.15
116.19
116.19
116.15
116.19
116.19
116.19
116.19
116.19
116.19
116.24
116.24
116.19
116.24
116.19
116.19
116.15
116.15
116.19
116.15
116.19
116.11
112.20
100.04
93.42
81.43
74.80
62.77
56.23
44.20
37.57
25.63
18.95
6.97
0.38
-11.65
-18.23
-30.22
-36.89
-48.92
-55.51
-67.45
-74.12
-86.15
-92.72
-104.72
-114.22
Y
-99.79
-93.16
-81.18
-74.54
-62.58
-55.93
-43.94
-37.40
-25.37
-18.70
-6.72
-0.09
11.90
18.49
30.51
37.10
49.09
55.76
67.75
74.38
86.36
93.03
104.85
112.24
112.24
112.24
112.24
112.24
112.24
112.24
112.24
112.24
112.24
112.24
112.24
112.24
112.24
112.20
112.24
112.24
112.24
112.24
112.29
112.24
112.24
112.25
112.25
112.25
April 21, 2000
HT16270
Pad Description
Pad No.
Pad Name
I/O
Description
1
DATA
I/O Serial data input/output with pull-high resistor
2
VSS
¾
Negative power supply, ground
3
OSCI
I
Crystal oscillator input pin
4
OSCO
O
Crystal oscillato output pin
5
VDD
¾
Positive power supply
6
VLCD
I
LCD operating voltage input pad.
7
IRQ
O
Time base or watchdog timer overflow flag, NMOS open drain
output
8, 9
BZ, BZ
O
2kHz or 4kHz tone frequency output pair (Tristate output
buffer)
10~13
T1~T4
I
Not connected
14~29
COM0~COM15
O
LCD common outputs
30~93
SEG0~SEG63
O
LCD segment outputs
I
Chip selection input with pull-high resistor. When the CS is
logic high, the data and command read from or write to the
HT16270 are disabled. The serial interface circuit is also reset.
But if the CS is at logic low level and is input to the CS pad, the
data and command transmission between the host controller
and the HT16270 are all enabled.
94
CS
95
RD
I
READ clock input with pull-high resistor. Data in the RAM of
the HT16270 are clocked out on the rising edge of the RD signal. The clocked out data will appear on the data line. The host
controller can use the next falling edge to latch the clocked out
data.
96
WR
I
WRITE clock input with pull-high resistor. Data on the DATA
line are latched into the HT16270 on the rising edge of the WR
signal.
Absolute Maximum Ratings
Supply Voltage .............................-0.3V to 5.5V
Storage Temperature.................-50°C to 125°C
Input Voltage .................VSS-0.3V to VDD+0.3V
Operating Temperature ..............-25°C to 75°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.
5
April 21, 2000
HT16270
D.C. Characteristics
Symbol
Parameter
VDD
Operating Voltage
IDD1
Operating Current
IDD2
Operating Current
ISTB
Standby Current
VIL
Input Low Voltage
VIH
Input High Voltage
IOL1
BZ, BZ, IRQ
IOH1
BZ, BZ
IOL2
DATA
IOH2
DATA
IOL3
LCD Common Sink Current
IOH3
LCD Common Source Current
IOL4
LCD Segment Sink Current
IOH4
LCD Segment Source Current
RPH
Pull-high Resistor
Ta=25°C
Test Conditions
VDD
Conditions
¾
¾
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
Min. Typ. Max. Unit
2.7
¾
5.2
V
No load/LCD ON
Crystal oscillator
¾
30
75
mA
¾
50
125
mA
No load/LCD OFF
Crystal oscillator
¾
5
25
mA
¾
10
45
mA
No load
Power down mode
¾
2
14
mA
¾
4
28
mA
0
¾
0.6
V
0
¾
1.0
V
2.4
¾
3
V
4.0
¾
5
V
DATA, WR, CS, RD
DATA, WR, CS, RD
3V
VOL=0.3V
0.9
1.8
¾
mA
5V
VOL=0.5V
1.7
3
¾
mA
3V
VOH=2.7V
-0.9
-1.8
¾
mA
5V
VOH=4.5V
-1.7
-3
¾
mA
3V
VOL=0.3V
0.9
1.8
¾
mA
5V
VOL=0.5V
1.7
3
¾
mA
3V
VOH=2.7V
-0.9
-1.8
¾
mA
5V
VOH=4.5V
-1.7
-3
¾
mA
3V
VOL=0.3V
80
160
¾
mA
5V
VOL=0.5V
180
360
¾
mA
3V
VOH=2.7V
-40
-80
¾
mA
5V
VOH=4.5V
-90
-180
¾
mA
3V
VOL=0.3V
50
100
¾
mA
5V
VOL=0.5V
120
240
¾
mA
3V
VOH=2.7V
-30
-60
¾
mA
5V
VOH=4.5V
-70
-140
¾
mA
100
200
300
kW
50
100
150
kW
3V
5V
DATA, WR, CS, RD
6
April 21, 2000
HT16270
A.C. Characteristics
Symbol
Parameter
fSYS
System Clock
fLCD
LCD Frame Frequency
tCOM
LCD Common Period
fCLK1
Serial Data Clock (WR Pin)
fCLK2
Serial Data Clock (RD Pin)
tCS
Serial Interface Reset Pulse
Width
(Figure 3)
tCLK
WR, RD Input Pulse Width
(Figure 1)
Ta=25°C
Test Conditions
Min.
Typ.
¾
32
¾
kHz
¾
32
¾
kHz
¾
64
¾
Hz
¾
64
¾
Hz
¾
n/fLCD
¾
sec
¾
¾
150
kHz
¾
¾
300
kHz
¾
¾
75
kHz
¾
¾
150
kHz
¾
250
¾
ns
Write mode
3.34
¾
¾
Read mode
6.67
¾
¾
Write mode
1.67
¾
¾
Read mode
3.34
¾
¾
¾
¾
120
¾
ns
Conditions
VDD
3V
Crystal oscillator
5V
3V
Crystal oscillator
5V
n: Number of COM
¾
3V
Duty cycle 50%
5V
3V
Duty cycle 50%
5V
CS
¾
3V
5V
3V
Max. Unit
ms
ms
tr, tf
Rise/Fall Time Serial Data Clock
Width
(Figure 1)
tsu
Setup Time for DATA to WR, RD 3V
Clock Width
(Figure 2) 5V
¾
¾
120
¾
ns
th
Hold Time for DATA to WR, RD 3V
Clock Width
(Figure 2) 5V
¾
¾
120
¾
ns
tsu1
3V
Setup Time for CS to WR, RD
Clock Width
(Figure 3) 5V
¾
¾
100
¾
ns
th1
3V
Hold Time for CS to WR, RD
Clock Width
(Figure 3) 5V
¾
¾
100
¾
ns
5V
7
April 21, 2000
HT16270
V A L ID D A T A
tf
W R , R D
C lo c k
D B
tr
9 0 %
5 0 %
1 0 %
tC
- V
tC
L K
D D
ts
G N D
V
5 0 %
Figure 1
S
- V
5 0 %
ts
W R , R D
C lo c k
th
u 1
- G N D
D D
G N D
1
- V
5 0 %
F IR S T
C lo c k
D D
Figure 2
tC
C S
D D
G N D
th
u
W R , R D
C lo c k
L K
V
5 0 %
D D
G N D
L A S T
C lo c k
Figure 3
Functional Description
Display memory - RAM structure
Time base and watchdog timer - WDT
The static display RAM is organized into 256´4
bits and stores the display data. The contents of
the RAM are directly mapped to the contents of
the LCD driver. Data in the RAM can be
accessedbytheREAD,WRITEand
READ-MODIFY-WRITE commands. The following is a mapping from the RAM to the LCD
patterns.
The time base generator and WDT share the
same divided (/256) counter. TIMER DIS/EN/CLR,
WDT DIS/EN/CLR and IRQ EN/DIS are independent from each other. Once the WDT
time-out occurs, the IRQ pin will remain at
logic low level until the CLR WDT or the IRQ
DIS command is issued.
C O M 1 5
C O M 1 4
C O M 1 3
C O M 3
C O M 1 2
C O M 2
C O M 1
C O M 0
S E G 0
3
0
S E G 1
7
4
S E G 2
1 1
8
S E G 3
1 5
1 2
S E G 6 3
2 5 5
2 5 2
D 3
D 2
D 1
D 0
A d d r
D 3
D a ta
D 2
D 1
D 0
A d d r e s s 8 B its
(A 7 , A 6 , ...., A 0 )
A d d r
D a ta
D a ta 4 B its
(D 3 , D 2 , D 1 , D 0 )
RAM mapping
8
April 21, 2000
HT16270
T im e B a s e
C lo c k S o u r c e
T IM E R
/2 5 6
V
C L R T im e r
W D T
/4
W D T E N /D IS
D D
Q
D
C K
C L R
IR Q
E N /D IS
IR Q
E N /D IS
R
W D T
Timer and WDT configurations
The following are the data mode ID and the
command mode ID:
If an external clock is selected as the source of
system frequency, the SYS DIS command turns
out invalid and the power down mode fails to be
carried out until the external clock source is removed.
Operation
Buzzer tone output
A simple tone generator is implemented in the
HT16270. The tone generator can output a pair
of differential driving signals on the BZ and BZ
which are used to generate a single tone.
ID
READ
Data
110
WRITE
Data
101
READ-MODIFY-WRITE
Data
101
COMMAND
Command 1 0 0
If successive commands have been issued, the
command mode ID can be omitted. While the
system is operating in the non-successive command or the non-successive address data mode,
the CS pin should be set to ²1² and the previous
operation mode will be reset also. The CS pin
returns to ²0², a new operation mode ID should
be issued first.
Command format
The HT16270 can be configured by the software
setting. There are two mode commands to configure the HT16270 resource and to transfer
the LCD display data.
Name
Mode
Command Code
Function
TONE OFF
0000-1000-X
Turn-off tone output
TONE 4K
010X-XXXX-X
Turn-on tone output, tone frequency is 4kHz
TONE 2K
0110-XXXX-X
Turn-on tone output, tone frequency is 2kHz
9
April 21, 2000
HT16270
Timing Diagrams
READ mode (command code : 1 1 0)
C S
W R
R D
D A T A
1
0
1
A 7
A 5
A 6
A 4
A 3
A 2
A 1
A 0
D 0
M e m o ry A d d re s s 1 (M A 1 )
D 1
D 2
D 3
1
0
1
D a ta (M A 1 )
A 7
A 5
A 6
A 4
A 3
A 2
A 1
A 0
D 0
D 1
D 2
D 3
D a ta (M A 2 )
M e m o ry A d d re s s 2 (M A 2 )
READ mode (successive address reading)
C S
W R
R D
D A T A
1
1
0
A 7
A 6
A 5
A 4
A 3
M e m o ry A d d re s s (M A )
A 2
A 1
A 0
D 0
D 1
D 2
D a ta (M A )
10
D 3
D 0
D 1
D 2
D a ta (M A + 1 )
D 3
D 0
D 1
D 2
D a ta (M A + 2 )
D 3
D 0
D 1
D 2
D 3
D 0
D a ta (M A + 3 )
April 21, 2000
HT16270
WRITE mode (command code : 1 0 1)
C S
W R
D A T A
1
1
0
A 7
A 5
A 6
A 3
A 4
A 1
A 2
A 0
D 0
M e m o ry A d d re s s 1 (M A 1 )
D 1
D 2
D 3
1
0
D a ta (M A 1 )
1
A 7
A 6
A 5
A 3
A 4
A 1
A 2
A 0
D 0
M e m o ry A d d re s s 2 (M A 2 )
D 1
D 2
D 3
D a ta (M A 2 )
WRITE mode (successive address writing)
C S
W R
D A T A
1
0
1
A 7
A 6
A 5
A 4
A 3
M e m o ry A d d re s s (M A )
A 2
A 1
A 0
D 0
D 1
D 2
D a ta (M A )
11
D 3
D 0
D 1
D 2
D a ta (M A + 1 )
D 3
D 0
D 1
D 2
D a ta (M A + 2 )
D 3
D 0
D 1
D 2
D 3
D 0
D a ta (M A + 3 )
April 21, 2000
HT16270
READ-MODIFY-WRITE mode (command code : 1 0 1)
C S
W R
R D
D A T A
1
1
0
A 7
A 6
A 5
A 4
A 3
A 2
A 1
A 0
M e m o ry A d d re s s 1 (M A 1 )
D 0
D 1
D 2
D 3
D 0
D a ta (M A 1 )
D 1
D 2
D 3
1
0
D a ta (M A 1 )
A 7
1
A 6
A 1
A 0
M e m o ry A d d re s s 2 (M A 2 )
D 0
D 1
D 2
D 3
D a ta (M A 2 )
READ-MODIFY-WRITE mode (successive address accessing)
C S
W R
R D
D A T A
1
0
1
A 7
A 6
A 5
A 4
A 3
M e m o ry A d d re s s (M A )
A 2
A 1
A 0
D 0
D 1
D 2
D 3
D a ta (M A )
D 0
D 1
D 2
D a ta (M A )
12
D 3
D 0
D 1
D 2
D a ta (M A + 1 )
D 3
D 0
D 1
D 2
D a ta (M A + 1 )
D 3
D 0
D 1
D 2
D 3
D 0
D a ta (M A + 2 )
April 21, 2000
HT16270
Command mode (command code : 1 0 0)
C S
W R
D A T A
1
0
0
C 8
C 7
C 6
C 5
C 4
C 3
C o m m a n d 1
C 2
C 1
C 0
C 8
C o m m a n d ...
C 7
C 6
C 5
C 4
C 3
C 2
C 1
C 0
C o m m a n d i
C o m m a n d
o r
D a ta M o d e
Mode (data and command mode)
C S
W R
D A T A
C o m m a n d
o r
D a ta M o d e
A d d re s s a n d D a ta
C o m m a n d
o r
D a ta M o d e
A d d re s s a n d D a ta
C o m m a n d
o r
D a ta M o d e
A d d re s s a n d D a ta
R D
13
April 21, 2000
HT16270
Application Circuits
V D D
C S
*
*V R
R D
V L C D
W R
D A T A
m C
B Z
H T 1 6 2 7 0
P ie z o
*R
B Z
IR Q
O S C I
C O M 0 ~ C O M 1 5
S E G 0 ~ S E G 6 3
C r y s ta l 3 2 7 6 8 H z o s c illa to r
O S C O
1 /5 B ia s , 1 /1 6 D u ty
L C D
*Note:
P a n e l
The connection of IRQ and RD pin can be selected depending on the requirement of the mC.
The voltage applied to VLCD pin must be lower than VDD.
Adjust VR to fit LCD display, at VDD=5V, VLCD=4V, VR=15kW±20%.
Adjust R (external pull-high resistance) to fit user¢s time base clock.
14
April 21, 2000
HT16270
Command Summary
Name
ID
Command Code
D/C
Function
Def.
READ
1 1 0 A7A6A5A4A3A2A1A0D0D1D2D3
D
Read data from the RAM
WRITE
1 0 1 A7A6A5A4A3A2A1A0 D0D1D2D3
D
Write data to the RAM
READMODIFYWRITE
1 0 1 A7A6A5A4A3A2A1A0 D0D1D2D3
D
Read and Write data to the RAM
SYS DIS
1 0 0 0000-0000-X
C
Turn off both system oscillator
and LCD bias generator
SYS EN
1 0 0 0000-0001-X
C
Turn on system oscillator
LCD OFF
1 0 0 0000-0010-X
C
Turn off LCD display
LCD ON
1 0 0 0000-0011-X
C
Turn on LCD display
TIMER DIS 1 0 0 0000-0100-X
C
Disable time base output
WDT DIS
1 0 0 0000-0101-X
C
Disable WDT time-out flag output Yes
TIMER EN 1 0 0 0000-0110-X
C
Enable time base output
WDT EN
1 0 0 0000-0111-X
C
Enable WDT time-out flag output
TONE OFF 1 0 0 0000-1000-X
C
Turn off tone outputs
CLR TIMER 1 0 0 0000-1101-X
C
Clear the contents of the time base
generator
CLR WDT
1 0 0 0000-1111-X
C
Clear the contents of the WDT stage
TONE 4K
1 0 0 010X-XXXX-X
C
Tone frequency output: 4kHz
TONE 2K
1 0 0 0110-XXXX-X
C
Tone frequency output: 2kHz
IRQ DIS
1 0 0 100X-0XXX-X
C
Disable IRQ output
IRQ EN
1 0 0 100X-1XXX-X
C
Enable IRQ output
F1
1 0 0 101X-0000-X
C
Time base clock output: 1Hz
The WDT time-out flag after: 4s
F2
1 0 0 101X-0001-X
C
Time base clock output: 2Hz
The WDT time-out flag after: 2s
F4
1 0 0 101X-0010-X
C
Time base clock output: 4Hz
The WDT time-out flag after: 1s
F8
1 0 0 101X-0011-X
C
Time base clock output: 8Hz
The WDT time-out flag after: 1/2 s
F16
1 0 0 101X-0100-X
C
Time base clock output: 16Hz
The WDT time-out flag after: 1/4 s
15
Yes
Yes
Yes
Yes
Yes
April 21, 2000
HT16270
Name
ID
Command Code
D/C
Function
Def.
F32
1 0 0 101X-0101-X
C
Time base clock output: 32Hz
The WDT time-out flag after: 1/8 s
F64
1 0 0 101X-0110-X
C
Time base clock output: 64Hz
The WDT time-out flag after: 1/16 s
F128
1 0 0 101X-0111-X
C
Time base clock output: 128Hz
Yes
The WDT time-out flag after: 1/32 s
TEST
1 0 0 1110-0000-X
C
Test mode, user don¢t use.
NORMAL
1 0 0 1110-0011-X
C
Normal mode
Yes
Note: X : Don¢t care
A7~A0 : RAM address
D3~D0 : RAM data
D/C : Data/Command mode
Def. : Power on reset default
All the bold forms, namely 1 1 0, 1 0 1, and 1 0 0, are mode commands. Of these, 1 0 0 indicates the
command mode ID. If successive commands have been issued, the command mode ID except for the
first command will be omitted. The source of the tone frequency and of the time base/WDT clock frequency can be derived from a 32.768kHz crystal oscillator or an external 32kHz clock. Calculation of
the frequency is based on the system frequency sources as stated above. It is recommended that the
host controller should initialize the HT16270 after power on reset, for power on reset may fail, which
in turn leads to malfunctioning of the HT16270.
16
April 21, 2000
HT16270
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.
17
April 21, 2000