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65
Real time clock module
Specifications (characteristics)
Absolute Max. rating
Symbol
Operating range
Item
Operating voltage
Frequency characteristics and current consumption
characteristics
Symbol
Condition
Electrical characteristics
Item
“H” input voltage (1)
“L” input voltage (1)
Input leak current (1)
Input leak current (2)
“L” output voltage (1)
“H” output voltage
“L” output voltage (2)
Off leak current
External dimensions
RTC-72421
Terminal connection
RTC-72421
(Unit: mm)
23.1 max.
3
0
6
4
1
18
2
17
3
16
4
15
5
14
6
13
7
12
8
11
9
10
RTC72421 A
EPSON 5053C
RTC72423 A
EPSON 6150
(V
DD
) and V
DD
are to have the same level of voltage
.
Do not connect it to any external terminals.
NC is not connected internally.
1
24
2
23
3
22
4
21
5
20
6
19
7
18
8
17
9
16
10
15
11
14
12
13
RTC-72423
RTC-72423
0.05 min.
2.8 max.
7.62
0.25
2
16.3 max.
7
1
0
1.0
0
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
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
STD. P
CS
0
ALE
A
0
A
1
A
2
A
3
RD
GND
WR
D
3
D
2
D
1
D
0
CS
1
(V
DD
)
(V
DD
)
V
DD
72423
STD. P
CS
0
NC
ALE
A
0
NC
A
1
NC
A
2
A
3
RD
GND
WR
D
3
D
2
D
1
NC
NC
D
0
CS
1
NC
(V
DD
)
(V
DD
)
V
DD
72421
90
°
to
105
°
0
°
to
10
°
4-bit REAL TIME CLOCK MODULE
RTC-72421
/
72423
Builtin crystal unit allows adjustment-free efficient operation.
ALE input terminal available for 8048, 8051, and 8085 series.
12/24H clock switchover function and automatic leap year setting.
Interrupt masking.
30 second adjustment function.
Low current consumption and features a backup function.
Item
Power source voltage
Input and output voltage
Storage temperature
Soldering condition
V
DD
V
I/O
T
STG
T
SOL
Condition
Ta=25C
Ta=25C
RTC-72421
RTC-72423
RTC-72421
RTC-72423
Specifications
-0.3 to 7.0
GND -0.3 to V
DD
+0.3
-55 to +85
-55 to +125
Under 260C within 10 sec.
(lead part) (package should
be less than 150C)
Twice at under 260C within
Unit
V
C
Operating temperature
Data holding voltage
CSI data holding time
Operation restoring time
Symbol
V
DD
T
OPR
V
DH
t
CDR
t
R
Condition
RTC-72421
RTC-72423
Refer to the data
holding timing
Specifications
4.5 to 5.5
-10 to 70
-40 to 85
2.0 to 5.5
2.0 min.
Unit
V
C
V
μs
Item
Frequency tolerance
Frequency temperature
characteristics
Aging
Shock resistance
Current consumption
f/fo
fa
S.R.
I
DD1
I
DD2
Ta=25C
V
DD
=5V
72421 A
72421 B
72423 A
72423
Three drops on a
hard board from 75 cm
or 3000G x 0.3ms x
1/2 sine wave x 3 directions
CS
1
=0V
Exclude input/
output current
V
DD
=5V
V
DD
=2V
Specifications
±10
±50
±20
±50
+10/-120
±5 max.
±10 max.
10 max.
5 max.
Unit
ppm
ppm/Y
ppm
μA
Input capacity
“H” input voltage (2)
“L” input voltage (2)
Symbol
V
IH1
V
IL1
I
LK1
I
LK2
V
OL1
V
OH
V
OL2
I
OFFLK
C
1
V
IH2
V
IL2
Condition
—
V
1
=V
DD
/0V
I
OL
=2.5mA
I
OH
=-400μA
I
OL
=2.5mA
V
1
=V
DD
/0V
frequency 1 MHz
V
DD
=2to5.5V
Min.
2.2
—
2.4
—
4/5 V
DD
—
Typ.
—
10
20
—
Max.
—
0.8
±1
±10
0.4
—
0.4
10
—
1/5 V
DD
Unit
V
μA
V
μA
pF
V
Applicable
terminal
All inputs
other than
CS
1
Input other
0
to D
3
D
0
to D
3
STD.P
Input other
0
to D
3
D
0
to D
3
CS
1
(25C reference temperature)
V
DD
=5V, Ta=25C,
Actual size