MSM58321 Datasheet, PDF (1/16 Pages) OKI electronic componets – REAL TIME CLOCK/CALENDAR

¡ _¡ Semicond_Suc_etor_miconductor
MSM58321
REAL TIME CLOCK/CALENDAR
MSM58321
DESCRIPTION
The MSM 58321 is a metal gate CMOS Real
Time Clock/Calendar with a battery backup
function for use in bus-oriented micropro-
cessor applications.
The time is read with 4-bit DATA I/O, AD-
DRESS WRITE, READ, and BUSY; it is written
with 4-bit DATA I/O, ADDRESS WRITE,
WRITE, and BUSY.
The 4-bit bidirectional bus line method is used
for the data I/O circuit; the clock is set, cor-
rected, or read by accessing the memory.
FEATURES
• 7 Function-Second, Minute, Hour, Day,
Day-of-Week, Month, Year
• Automatic leap year calender
• 12/24 hour format
• Frequency divider 5-poststage reset
• Reference signal output
• 32.768 kHz crystal controlled operation
• Single 5V power supply
• Back-up battery operation to VDD = 2.2V
• Low power dissipation
90 µW max. at VDD = 3V
2.5 mW max. at VDD = 5V
• 16 pin plastic DIP (DIP 16-P-300)
FUNCTIONAL BLOCK DIAGRAM
5-poststage (O11~O15) _{1024 Hz}
XT RFB
XT
OSC
BUSY
STOP
TEST
N
Rp
Rp
WRITE
Rp
READ
Rp
CS1
Rp
CS2
Rp
D0
D1
D2
D3
ADDRESS
WRITE
Rp
1
2¹⁵ R
BUSY
R
WRIETE
1 Hz
E-F
TEST
D
1/60 Hz
1/3600 Hz
\DATA BUS
44
3
43
43
SWITCH _{S1 S10 MI1 MI10 H1 H10}
W
1 Hz
WRITE
1/10 1/6
SECOND
1/10 1/6
MINUTE
1/12 or 1/24
HOUR
1/7
WEEK
S1 S10 MI1 MI10 H1 H10 W
READ
CS
TRI-STATE
CONTROL
ADDRESS ADDRESS
LATCH
DECODER
S1
0 _S10
1 _MI1
2 _MI10
3 _H1
4
5
6
7
8
9
A
B
C
D
E-F
H10
W
D1
D10
MO1
MO10
Y1
Y10
D
E-F
DATA BUS
TEST-P
44
4
D1 D10 MO1 MO10
1/10 1/3
DAY
WRITE
D1 D10
1/12
MONTH
MO1 MO10
44
Y1 Y10
1/10 1/10
YEAR
Y1 Y10
Rp = 200 k TYP
7