Real time clock module
4-bit REAL TIME CLOCK MODULE
Product number (please refer to page 2)
RTC-72421/72423
Q42 7 2 4 2 1 x x x x x 0 0
Q42 7 2 4 2 3 x x x x x 0 0
• Built-in crystal unit allows adjustment-free efficient operation.
• 12/24 h clock switchover function and automatic leap year setting.
• Interrupt masking.
Actual size
RTC-72421
RTC-72423
The details are mentioned in the application manual.
http://www.epsondevice.com
Specifications (characteristics)
Absolute Max. rating
Symbol
Item
V
DD
Supply voltage
V
I/O
Input and output voltage
Storage temperature
∗
T
STG
Condition
Ta=+25 °C
Ta=+25 °C
RTC-72421
RTC-72423
Min.
-0.3
GND -0.3
-55
-55
Max.
7.0
V
DD
+0.3
+85
+125
Unit
V
°C
Terminal connection
RTC-72421
#18
#10
No.
1
2
3
4
5
6
7
8
9
No.
1
2
3
4
5
6
7
8
9
10
11
12
Pin terminal No.
18
STD. P
17
CS
0
16
ALE
15
A
0
14
A
1
A
2
13
A
3
12
RD
11
GND
10
Pin terminal No.
24
STD. P
23
CS
0
22
NC
21
ALE
20
A
0
19
NC
18
A
1
17
NC
16
A
2
15
A
3
14
RD
13
GND
Pin terminal
V
DD
(V
DD
)
(V
DD
)
CS
1
D
0
D
1
D
2
D
3
WR
∗
Stored as bare product after unpacking
#1
#9
Operating range
Item
Power voltage
Supply voltage
Operating temperature
∗
Symbol
V
DD
V
CLK
T
OPR
Condition
—
—
RTC-72421
RTC-72423
Min.
4.5
2.0
-10
-40
Max.
5.5
5.5
70
85
°C
Unit
V
V
RTC-72423
#24
#13
Pin terminal
V
DD
(V
DD
)
(V
DD
)
NC
CS
1
D
0
NC
NC
∗
No condensation
Frequency characteristics
Item
Frequency tolerance
Symbol
Condition
72421 A
72421 B
Ta=+25
°C
∆f/fo
72423 A
VDD=5 V
72423
-10
°C
to +70
°C
(Reference at +25
°C)
T
OP
-40
°C
to +85
°C
(Reference at +25
°C)
Ta=+25
°C
f/V
VDD=2.0 V to 5.5 V
fa
VDD=5 V, Ta=+25
°C,
first year
Range
±10
±50
±20
±50
+10/-120
+10/-220
±5
Max.
±5
Max.
x 10
-6
/V
x 10
/year
-6
#1
#12
D
1
D
2
D
3
WR
Unit
(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.
-6
x 10
Frequency temperature
characteristics
Frequency voltage
characteristics
Aging
External dimensions
RTC-72421
(DIP 18-pin)
23.1 Max.
6.3
(Unit: mm)
RTC72421 A
EPSON 1234A
7.62
0.2 Min.
0.25
DC characteristics
Item
Current consumption
“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
Input capacity
“H” input voltage (2)
“L” input voltage (2)
Symbol Condition Min. Typ. Max.
CS
1
=0 V
V
DD
=5 V
I
DD1
1 10
Exclude input/
—
I
DD2
output current
V
DD
=2 V
0.9 5
2.2
V
IH1
—
—
V
IL1
0.8
I
LK1
±1
V
1
=V
DD
/0 V
—
I
LK2
—
±10
V
OL1
I
OL
=2.5 mA
0.4
V
OH
I
OH
=-400
µA
2.4
—
V
OL2
I
OL
=2.5 mA
0.4
I
OFFLK
V
1
=V
DD
/0 V
10
—
10
Input
C
1
frequency 1 MHz
20 —
4/5 V
DD
V
IH2
—
V
DD
=2 to 5.5 V
—
V
IL2
1/5 V
DD
Unit
µA
V
µA
Applicable
terminal
4.2
90° to 105°
2.54
0.65 Max.
3.3 Min.
12.2 Max.
7.9
—
All inputs
other than
CS
1
Input other
than D
0
to D
3
RTC-72423
(SOP 24-pin)
16.3 Max.
D
0
to D
3
V
µA
pF
V
STD.P
Input other
than D
0
to D
3
EPSON 1234A
RTC72423 A
D
0
to D
3
CS
1
1.27
0.35
0.1 Min.
2.8 Max.
0° to 10°
1.0
0.2
94
Microcontroller MCU
京公网安备 11010802033920号
EEWORLD
