¡ Semiconductor
MSM62X42B
¡ Semiconductor
REAL TIME CLOCK IC WITH BUILT-IN CRYSTAL
DESCRIPTION
The MSM62X42B is a bus-connection Micro-
computer peripheral IC of a Real Time Clock
with built-in crystal in the perpetual calendar
which can be read and written from a second
unit. The interface between this IC and a
microcomputer uses 4 data buses, 4 address
buses, 3 control buses and 2 chip selects and
carries out setting up, amending and reading
time.
ALE input is available for 8048 system, 8051
system or 8085 system and is used for other
microcomputers if this input is fixed at "H".
MSM62X42B
The clock function provides seconds, min-
utes, hours, day of week, date, month, year,
12/24 hour selectable, automatic leap year in
the Christian Era and 30-second compensa-
tion controlled by software. The periodical
interrupt function (or periodical waveform
output) and the STOP/START function of the
clock are also provided. The device is a silicon
gate CMOS and the current consumption is
low. The built-in crystal oscillator is 32.768
kHz and battery backup operation is consid-
ered.
FEATURES
• 32.768kHz built-in crystal oscillator
(2 ranks of
±10PPM
and
±50PPM
---
DIP)
(2 ranks of
±20PPM
and
±50PPM
---
SOP)
• Real time clock of second, minute, date,
month, year and day of week
• Interface corresponding to microcom-
puter bus
• 30-second compensation controlled by
software
• Periodical interrupt function (or
periodical waveform output) for alarm
• STOP/START function for clock
• 12/24 hour selectable
• AEL input for 8048 system, 8051 system
or 8085 system (when a microcomputer
does not provide the ALE output, fix the
AEL input at "H".)
• Low current consumption for CMOS
device
• Low STANDBY voltage and small
STANDBY current
• 18-pin plastic DIP(DIP18-P-300)
• 24-pin plastic SOP
PIN CONFIGURATION
MSM62X42BRS
(TOP View) 18 Lead Plastic DIP
STD.P 1
CS
0
ALE
A
0
A
1
A
2
A
3
RD
GND
2
3
4
5
6
7
8
9
STD.P
CS
0
NC
ALE
A0
NC
A
1
MSM62X42BGS-1K
(TOP View) 24 Lead Plastic SOP
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
V
DD
(V
DD
)
(V
DD
)
NC
CS
1
D
0
NC
NC
D
1
D
2
D
3
WR
18
V
DD
17 (V
DD
)
16 (V
DD
)
15
14
13
12
11
10
CS
1
D
0
D
1
D
2
D
3
WR
NC
A
2
A
3
RD
GND
NC : NO CONNECTION (unused pins)
Note:
The actual type name indicates the abbreviated one, M62X42B.
41
OKI [ OKI ELECTRONIC COMPONETS ]
