RTC-72421 Datasheet, PDF (1/2 Pages) Epson Company – Real time clock module(4-bit REAL TIME CLOCK MODULE)

Real time clock module
4-bit REAL TIME CLOCK MODULE
RTC-72421/72423
• Built-in crystal unit allows adjustment-free efficient operation.
• ALE input terminal available for 8048, 8051, and 8085 series.
• 12/24 h clock switchover function and automatic leap year setting.
• Interrupt masking.
• 30 second adjustment function.
• Low current consumption and features a backup function.
Actual size
Specifications (characteristics)
Absolute Max. rating
Item
Symbol
Power source voltage
VDD
Input and output voltage VI/O
Storage temperature
TSTG
Soldering condition
TSOL
Condition
Specifications
Unit
Ta=+25 °C
-0.3 to 7.0
Ta=+25 °C GND -0.3 to VDD+0.3 ^V
RTC-72421
-55 to +85
RTC-72423
-55 to +125
°C
RTC-72421
Under +260 °C within 10 s
(lead part) (package should
be less than +150 °C)
Twice at under +260 °C within 10
RTC-72423 _{s or under +230 °C within 3 min.}
Operating range
Item
Operating voltage
Operating temperature
Data holding voltage
Symbol
VDD
TOPR
VDH
Condition
RTC-72421
RTC-72423
Specifications Unit
4.5 to 5.5
V
-10 to 70
°C
-40 to 85
2.0 to 5.5
V
CSI data holding time
tCDR _{Refer to the data}
Operation restoring time
tR
holding timing
2.0 Min.
µs
Frequency characteristics and current consumption
characteristics
Item
Frequency tolerance
Symbol
Condition
72421 A
Ta=+25 °C 72421 B
∆f/fo
VDD=5 V 72423 A
72423
Specifications
±10
±50
±20
±50
Unit
x 10^-6
Frequency temperature
characteristics
Aging
Shock resistance
Current consumption
fa
S.R.
IDD1
IDD2
-10 °C to +70 °C
(+25 °C reference temperature)
VDD=5 V, Ta=+25 °C,
first year
Three drops on a
hard board from 750 mm
or 29400 m/s² x 0.3 ms x
1/2 sine wave x 3 directions
CS1=0 V VDD=5 V
Exclude input/
output current VDD=2 V
+10/-120
±5 Max.
±10 Max.
10 Max.
5 Max.
x 10^-6/year
x 10^-6
µA
DC characteristics
Item
“H” input voltage (1)
“L” input voltage (1)
Input leak current (1)
Input leak current (2)
“L” output voltage (1)
Symbol Condition
VIH1
—
VIL1
ILK1 _{V1=VDD/0 V}
ILK2
VOL1 IOL=2.5 mA
Min. Typ. Max.
2.2
—
0.8
±1
—
±10
—
0.4
Unit
V
Applicable
terminal
All inputs
other than
CS1
Input other
µA ^{than D0 to D3}
D0 to D3
“H” output voltage
VOH IOH=-400 µA 2.4
—V
“L” output voltage (2)
Off leak current
Input capacity
VOL2 IOL=2.5 mA
IOFFLK V1=VDD/0 V _—
C1
Input
frequency 1 MHz
0.4
10
10
20 —
STD.P
µA
Input other
pF ^{than D0 to D3}
D0 to D3
“H” input voltage (2) _{VIH2 VDD=2 to 5.5 V} 4/5 VDD _—
V
77
“L” input voltage (2) _VIL2
—
1/5 VDD
CS1
Terminal connection
RTC-72421
No. 72421 No. 72423
18 17 16 15 14 13 12 11 10
1
STD. P 1
STD. P
2
CS0
2
CS0
3
ALE
3
NC
4
A0
4
ALE
5
A1
5
A0
6
A2
6
NC
7
A3
7
A1
8
RD
8
NC
9
GND
9
A2
1 2 3 4 56 7 8 9
10
WR
10
A3
11
D3
11
RD
RTC-72423
12
D2
12 GND
13
D1
13 WR
24 23 22 21 20 19 18 17 16 15 14 13
14
D0
14
D3
15
CS1
15
D2
16
(VDD) 16
D1
17
(VDD) 17
NC
18
VDD
18
NC
19
D0
20
CS1
21
NC
22 (VDD)
23 (VDD)
1 2 3 4 5 6 7 8 9 10 11 12
24
VDD
(VDD) and VDD are to have the same level of voltage. Do not connect it to any external terminals.
NC is not connected internally.
External dimensions
RTC-72421
23.1 Max.
(Unit: mm)
RTC72421 A
EPSON 5053C
7.62
2.54
0.65 Max.
0.25
90° to
105°
RTC-72423
16.3 Max.
RTC72423 A
EPSON 6150
0° to
1.27
0.05 Min.
0.35
2.8 Max.
10°
1.0