Real-Time Clock
5/DS12C87A
DC ELECTRICAL CHARACTERISTICS
(V
CC
= 0V, V = 3.0V, T = over the operating range, unless otherwise noted.) (Note 2)
BAT A
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
500
UNITS
nA
V
Current (OSC On);
BAT
I
(Note 8)
(Note 8)
BAT
T
A
= +25°C, V
= 3.0V
BACKUP
V
Current (Oscillator Off)
I
100
nA
BAT
BATDR
AC ELECTRICAL CHARACTERISTICS
(V
CC
= 4.5V to 5.5V, T = over the operating range.) (Note 2)
A
PARAMETER
SYMBOL
CONDITIONS
MIN
385
150
125
TYP
MAX
UNITS
ns
Cycle Time
t
DC
CYC
Pulse Width, DS Low or R/W High
Pulse Width, DS High or R/W Low
Input Rise and Fall
PW
ns
EL
PW
ns
EH
t , t
R
30
80
ns
F
R/W Hold Time
t
10
50
ns
RWH
R/W Setup Time Before DS/E
t
ns
RWS
Chip-Select Setup Time Before
DS or R/W
t
20
ns
CS
Chip-Select Hold Time
t
0
ns
ns
ns
ns
ns
ns
ns
ns
CH
Read-Data Hold Time
t
10
0
DHR
Write-Data Hold Time
t
DHW
Address Valid Time to AS Fall
Address Hold Time to AS Fall
Delay Time DS/E to AS Rise
Pulse Width AS High
t
30
10
20
60
40
ASL
AHL
ASD
t
t
PW
ASH
Delay Time, AS to DS/E Rise
t
ASED
Output Data Delay Time from DS
or R/W
t
20
120
ns
DDR
Data Setup Time
t
100
5
ns
µs
µs
µs
DSW
Reset Pulse Width
t
RWL
IRQ Release from DS
IRQ Release from RESET
t
2
2
IRDS
t
IRR
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