HT6750A
Date Printer
Block Diagram
Rev. 1.00
1
January 17, 2003
Features
Operating voltage: 2.4V~5.5V
Operating current: < 3
mA at 3.0V
Constant voltage output (1.8V
5%) at 2.4V~5.5V
operating for driving lamp (1.8V/40mA)
LCD contrast can not distort at 2.4V~5.5V operating
LCD display drive 1/3 duty, 1/2 bias, frame frequency
is 42.67Hz
At power interrupt, data hold up > 1.0s
(between V
DD
and V
SS
connect a 0.1
mF capacitor)
Built-in power on reset function
32K crystal oscillator (Internal capacitor and resistor)
Calendar and time adjustment
Date imprinting modes
(Y/M/D, D/H/Min, Imprint off, M/D/Y, D/M/Y)
Mode is selected by cyclically turning
4 film printing times is selectable or external input
control (30ms/45ms/60ms/external control)
Direct resetting system
Lamp output time control
Provides module test circuit
General Description
The 6-Digital Timer is a camera data optical printer. Dis-
playing and printing of data (Year Month Day/Day Hour:
Minute/OFF/Month Day Year/Day Month Year) can be
selected by mode selection. Date updating is a fully au-
tomatic calendar from the year 1998.1.1 to 2049.12.31.
O S C I
O S C O
O s c i l l a t o r
C o n t r o l
C i r c u i t
D i v . 3 2 K
T E S T 2
D i v . 6 0
D i v . 6 0
C O M 1 ~ C O M 3
S E G O N
R E S E T
M O D E
S E L
S E T
V . 2
V . 4
L C 1
L C 2
P r i n t / L a m p
C o n t r o l
T
D
X
I m - P r i n t M a r k
L a m p
D i v . 3 2 K
D i v . 2 8 , 2 9 ,
3 0 o r 3 1
D i v . 2 4
Y e a r
C o u n t e r
M U X
M U X
M U X
S E G 1
S E G 1 5
V D D
V S S
Pad Description
Pad No.
Pad Name
I/O
Internal
Connection
Description
1, 2
VSS
Negative power supply, ground
3,
19, 20
COM1
COM3, COM2
O
CMOS
Output for LCD panel common
4~18
SEG1~SEG15
O
CMOS
LCD segment output driver
21
MODE
I
CMOS with
Pull-high
Mode select input pin (Internal pull-high 75K)
22
SEL
I
CMOS with
Pull-high
Correction digit shift switch (Internal pull-high 75K)
23
SET
I
CMOS with
Pull-high
Correction digit data (Internal pull-high 75K)
24
SEGON
I
CMOS with
Pull-high
Est pin, if pull-low will force all segment
ON
25
RESET
I
CMOS with
Pull-low
External Reset input (Internal pull-low, 50K)
26
TEST1
I
CMOS with
Pull-low
Test pin (not for customer)
27
OSCO
O
CMOS
Crystal oscillator output pin
28
OSCI
I
CMOS
Crystal oscillator input pin
29, 30
VDD
Positive power supply
31
VF4
O
CMOS
Double reference voltage
32, 33
LC2, LC1
I
CMOS
Connected to 0.1
mF capacitor
34
VF2
O
CMOS
Reference voltage
35~40
RF1~RF6
I
Adjust regulator output voltage, TRIM PIN
41~44
TR1~TR4
I
Adjust constant voltage and drive lamp output pin (Open drain)
45
T
I
CMOS with
Pull-high
Imprint time select input (Internal pull-high 75K with
Latch type)
46
D
I
CMOS with
Pull-high
Imprint time external control input (Internal pull-high 75K with
Latch type)
47
X
I
CMOS with
Pull-high
Imprint trigger input pin (Internal pull-high 75K)*
48
TEST2
I
CMOS with
Pull-high
For coustomer test
PRINTING LCD use only, pull-low will force
Lamp
ON and other function is OK (Internal pull-high 75K)**
49
LAMP
O
CMOS
Drive lamp output pin (Open drain)
Note:
* The X input has no effect in OFF mode, selection and setting mode; the lamp will be turned off automatically.
** The TEST2 has no effect in selection and setting mode; the lamp will be turned off automatically.
Absolute Maximum Ratings
Supply Voltage .......................................................5.5V
Storage Temperature ............................
-20C to 60C
Input Voltage ......................................................... 5.5V
Operating Temperature...............................0
C to 50C
Static Electricity (OFF Power)...................................................................................200pF,
200V, 10 times to each pin
Note: These are stress ratings only. Stresses exceeding the range specified under
Absolute Maximum Ratings 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 reliabil-
ity.
HT6750A
Rev. 1.00
3
January 17, 2003
HT6750A
Rev. 1.00
5
January 17, 2003
Functional Description
6-digit timer in 5 modes: Mode selection for 3 key
applications
Date from 1-1-
98 to 31-12-49 (2049) automatic
updating, including leap years.
Matrix address LCD interface in 1/3 duty, 1/2 bias,
frame frequency is 43Hz.
Printing enable is
Go low trigger in X input. V
X
1/2
V
DD
, Debounce in printing trigger: 1ms
T
DEBOUNCE
2ms.
After printing,
will blink 3 times at 1Hz rate.
Print means lamp output
LOW to light lamp. Lamp
output sink current is 40mA Min. (Constant current
source ), typical 45mA (V
DD
=2.4V~5.5V).
Printing time: 30ms, 45ms, 60ms or programmable
(determined by the control CPU of the camera), se-
lected by D or T and Topt inputs.
Built-in crystal (32768Hz) oscillator circuit (capacitor
and resistor).
At
OFF mode ( - - - - - - ), printing (Lamp on) and
data setting is inhibited in any case and printing
mark OFF.
Default value at power on is
98 1 1 (ASIAN DATE ).
Date and time cannot be set with printing
mark
ON.
LCD segment test pin is provided, a
SEGON is
pull-low which will force all segments ON. This test pin
is normally pull-high through an on chip 1k
W resistor.
: mark is still at time mode, at time setting, digit se-
lected by SEL pin will blink at 1Hz and 1/2 duty rate.
At setting mode (SET), printing
mark is OFF and
printing is inhibited.
The selected digit (blinking) count up by one at short
intervals (1.0sec
T
SET
1.25sec), when the ON key is
pressed for less than 1.0sec; if the SET key is pressed
longer than 1.25sec, the digit will count up rapidly at
8Hz rate.
Printing is disabled during data and time setting.
Debounce time of MODE, SEL, SET key is:
ON recognition: when the ON key is pressed longer
than T
ON
, ON is recognized.
31.25ms
T
ON
62.5ms,
OFF recognition: when the ON key is pressed longer
than T
OFF
, OFF is recognized; the next input has to
wait.
31.25ms
T
OFF
62.5ms,
If at least one key-ON time pulse is detected during
the
T
OFF
period, the time before the key-ON pulse is
regarded as the key-ON time.
The lamp light-up time is controlled depending on the
levels of D and T pins.
D
T
Lamp signal output time
H
H
60ms
H
L
30ms
L
H
Depend on X input pulse width
L
L
45ms
X pin must be carefully protected, the system cannot
be reset when in
200V and 200pF one-shot test.
(add external resistor 10k
W series with the pad; its
better if it works well without the resistor)
At
OFF mode, no data can be set.
The X input is rejected in some condition, such as:
OFF mode
Selection and Setting mode (In these condition the
lamp must be turned off)
Power on reset and after crystal is stable (max. 2 sec)
Regulator output voltage accuracy is 2V
3.0% (after
TRIM)
Display in Day-Hour-Minute mode, in 24-hour system
(0~23)
Operation flowchart
Mode selection sequence and initial value: (
MODE
key)
In digit setting, press the
SET key
The digit selected will blink at a 1hz rate.
The blinking digit (selected digit) will count up by itself.
If
SET key is pressed 1sec, the digit will count up
rapidly at an 8Hz rate, otherwise count up by 1 every
time it
s pressed (1sec).
W h e n
t h e
c o l o n
(
:) is blinking in the
Day-Hour-Minute mode, pressing the SET key will re-
set the seconds to 00.
A s i a n C a l e n d a r
D a y , H o u r , M i n u t e
M
' Y M D
D H : M
O . .
A m e r i c a n C a l e n d a r E u r o p e a n C a l e n d a r
M
M D ' Y
D M ' Y
M
T
O N
T
O . .
A s i a n C a l e n d a r
D a y , H o u r , M i n u t e
O . .
A m e r i c a n C a l e n d a r E u r o p e a n C a l e n d a r
M
' 9 8 1 1
1 0 : 0 0
M
1 1 ' 9 8
1 1 ' 9 8
M
A s i a n C a l e n d a r
M
' 9 8 1 1
PDF 
ZIP
