Real-Time Clock
5/DS12C87A
Typical Operating Characteristics
(V
CC
= +5.0V, T = +25°C, unless otherwise noted.)
A
I
vs. V
BAT
BAT1
OSCILLATOR FREQUENCY
vs. TEMPERATURE
vs. V
CC
V
CC
= 0V
+85°C
32768.70
32768.60
300
250
200
150
+25°C
32768.50
32768.40
0°C
+70°C
32768.30
32768.20
32768.10
+40°C
-40°C
32768.00
3.0
4.0
2.5
2.8
3.3
(V)
3.5
3.8
4.5
4.8
5.0
5.5
5.3
V
BAT
V
(V)
CC
Functional Diagram
X1
X2
DIVIDE
BY 8
DIVIDE
BY 64
DIVIDE
BY 64
OSC
V
CC
16:1 MUX
GND
POWER
CONTROL
SQUARE-
WAVE
SQW
IRQ
GENERATOR
V
BAT
IRQ
GENERATOR
DS12885
CS
R/W
DS
REGISTERS A, B, C, D
CLOCK/CALENDAR
UPDATE LOGIC
BUS
INTERFACE
AS
CLOCK/CALENDAR AND
ALARM REGISTERS
MOT
RESET
BUFFERED CLOCK/
CALENDAR AND ALARM
REGISTERS
AD0–AD7
USER RAM
114 BYTES
RLCR
_____________________________________________________________________
7
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
