
Actual size
http://www.epsontoyocom.co.jp
Real time clock module
Epson Toyocom
Block diagram
Terminal connection/External dimensions
(Unit:mm)
Specifications (characteristics)
*Refer to application manual for details.
Absolute Max. rating
DC characteristics
Item
Symbol
Condition
Min.
Max.
Unit
Item
Symbol
Condition
Min.
Typ.
Max.
Unit Applicable terminal
Supply voltage
VDD
Ta=+25
°C
-0.3
+7.0
IDD1
VDD=5 V
1
10
-
Input voltage
VI/O
Ta=+25
°C
GND-0.3
VDD+0.3
V
Current consumption
IDD2
CS1= 0 V
Exclude input/
output current V
DD
=2 V
-
0.9
5
A
-
RTC-72421
-55
+85
HIGH input voltage (1)
VIH1
2.2
-
Storage
temperature *
TSTG
RTC-72423
-55
+125
°C
LOW input voltage (1)
VIL1
-
0.8
V
All inputs other than
CS1
*Stored as bare product after unpacking
LOW output voltage (1)
VOL1
IOL=2.5 mA
-
0.4
Operating range
HIGH output voltage
VOH
IOH=-400 A
2.4
-
D0 to D3
Item
Symbol
Condition
Min.
Max.
Unit
LOW output voltage (2)
VOL2
IOL=2.5 mA
0.4
V
Power voltage
VDD
-
4.5
5.5
OFF leak current
IOFFLK
V1=VDD/0 V
-
10/-10
A
STD.P
Clock voltage
VCLK
-
2.0
5.5
V
10
Input other than
D0 to D3
RTC-72421
-10
+70
Input capacity
C1
Input frequency
1 MH z
-
20
pF
D0 to D3, STD.P
Operating
temperature
TOPR
RTC-72423
-40
+85
°C
HIGH input voltage (2)
VIH2
4/5 VDD
-
Stored as bare produc after unpacking
LOW input voltage (2)
VIL2
VDD=2.0 V to 5.5 V
-
1/5 VDD
V
CS1
Frequency characteristics
Input leak current (1)
ILK1
1/-1
A
Input other than
D0 to D3
Item
Symbol
Condition
Range
Unit
Input leak current (2)
ILK2
V1=VDD/0 V
-
10/-10
D0 to D3
72421A
±10
72421B
±50
72423A
±20
Frequency
precision
f /f
Ta=+25 °C
VDD=5.0 V
72423
±50
-10
°C to +70 °C (+25 °C)
+10 / -120
Frequency
temperature
characteristics
TOP
-40
°C to +85 °C(+25 °C)
+10 / -220
×10
-6
Frequency voltage
characteristics
f/V
Ta=+25
°C,VDD=2.0 V to 5.5 V ±5.0 Max. ×10
-6/V
Aging
fa
Ta=+25
°C,VDD=5.0 V,First year ±5.0 Max. ×10
-6/year
OS C
R ESET
bi t
STOP
bit
30 sec AD J
bit
Counter
HOLD
bit
BU SY
bit
D3
D2
D1
D0
WR
RD
A3
A2
A1
A0
CS0
ALE
CS1
S1
S 10
MI1
M I10
H1
H10
W
D1
D 10
M O 1 MO 10
Y1
Y10
64 Hz
1 Sec ond carry
1 M inute c arry
1 H our c arry
S1 to
CF
CD
CE
CF
Gate
Latc h
De coder
24/12
bi t
RT C-7 2421 /724 23
STD. P
O u tput
Se le c to r
RTC-72421
RTC-72423
4-bit REAL TIME CLOCK MODULE
RTC - 72421
RTC - 72423
Built-in crystal unit allows adjustment-free efficient operation.
24 h /12 h changeable and leap year automatically adjustable
(Gregorian calendar).
Metal may be expo sed o n the top or bottom of th is pro duct. T his w ill not affect any qu ality, re liability o r electrical spec.
RTC-72 421 (DIP 18 -pin)
7 .62
0
° -15°
0.25
0.46
4.2
Max.
3.3
Min.
0.2
Min.
2.54
1.52
2 3.1 Ma x.
6.
3
#1
#18
#10
#9
RTC7 2421 A
EPSON
1234A
No .
Pin
te rmina l
No .
Pin
te rmina l
1
STD.P
18
VDD
2
/CS 0
17
(VDD)
3
AL E
16
(VDD)
4
A0
15
CS1
5
A1
14
C0
6
A2
13
D1
7
A3
12
D2
8
/RD
11
D3
9
GND
10
/W R
R TC -72423 (SOP 24-pin)
1.0
0.2
0
° - 10°
0.2
0
° - 10°
1.27
0.35
2.8 Max.
0.1 Min.
2.8 Max.
0.1 Min.
#12
#1
16.3 Max.
#24
#1 3
7
.9
12.
2M
ax
.
RTC 62423
EPSON 1 234A
#12
#1
16.3 Max.
#24
#1 3
7
.9
12.
2M
ax
.
RTC 72423
EPSON 1 234A
No .
Pin
te rmina l
No .
Pin
te rmina l
1
STD.P
24
VDD
2
/CS 0
23
(VDD)
3
N.C.
22
(VDD)
4
AL E
21
N.C.
5
A0
20
CS1
6
N.C.
19
D0
7
A1
18
N.C.
8
N.C.
17
N.C.
9
A2
16
D1
10
A3
15
D2
11
/RD
14
D3
12
GND
13
/WR
Product Number (Please contact us)
RTC-72421 : Q42724211xxxx00
RTC-72423 : Q42724231xxxx00