
DS12885/DS12887/DS12887A/DS12C887/DS12C887A
Real-Time Clocks
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7
Typical Operating Characteristics
(VCC = +5.0V, TA = +25°C, unless otherwise noted.)
OSCILLATOR FREQUENCY
vs. VCC
DS12885
toc02
VCC (V)
FREQUENCY
(Hz)
5.3
5.0
4.8
32768.10
32768.20
32768.30
32768.40
32768.50
32768.60
32768.70
32768.00
4.5
5.5
IBAT1 vs. VBAT
vs. TEMPERATURE
DS12885
toc01
VBAT (V)
I BAT
(nA)
3.8
2.8
3.0
3.3
3.5
200
300
250
150
2.5
4.0
VCC = 0V
+85
°C
+25
°C
0
°C
-40
°C
+70
°C
+40
°C
POWER
CONTROL
GND
OSC
BUS
INTERFACE
VCC
X1
X2
RESET
CS
DS
AS
R/W
MOT
AD0–AD7
DIVIDE
BY 8
DIVIDE
BY 64
DIVIDE
BY 64
16:1 MUX
SQUARE-
WAVE
GENERATOR
REGISTERS A, B, C, D
CLOCK/CALENDAR AND
ALARM REGISTERS
USER RAM
114 BYTES
CLOCK/CALENDAR
UPDATE LOGIC
IRQ
SQW
IRQ
GENERATOR
BUFFERED CLOCK/
CALENDAR AND ALARM
REGISTERS
VBAT
RLCR
DS12885
Functional Diagram