
DS1308
Low-Current I2C RTC with 56-Byte NV RAM
3
Maxim Integrated
DC ELECTRICAL CHARACTERISTICS
(VCC = 0V, VBAT = VBATMIN to VBATMAX, TA = -40NC to +85NC, unless otherwise noted.) (Note 2)
AC ELECTRICAL CHARACTERISTICS
(VCC = VCCMIN to VCCMAX, TA = -40NC to +85NC, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Battery Current, SQW Off
(Note 5)
IBAT1
VBAT = 3V
250
nA
VBAT = VBATMAX
600
Battery Current, SQW On
(Note 6)
IBAT2
VBAT = 3V
550
nA
VBAT = VBATMAX
1100
Data-Retention Current (Note 7)
IBATDAT
VBAT = 3V
25
100
nA
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
SCL Clock Frequency
fSCL
(Note 8)
0.03
400
kHz
Bus Free Time Between a STOP
and START Condition
tBUF
1.3
F
s
Hold Time (Repeated) START
Condition
tHD:STA
(Note 9)
0.6
F
s
Low Period of SCL Clock
tLOW
1.3
F
s
High Period of SCL Clock
tHIGH
0.6
F
s
Data Hold Time
tHD:DAT
(Notes 10, 11)
0
0.9
F
s
Data Setup Time
tSU:DAT
(Note 12)
100
ns
Setup Time for a Repeated
START Condition
tSU:STA
0.6
F
s
Rise Time of Both SDA and SCL
Signals
tR
(Note 13)
20 +
0.1CB
300
ns
Fall Time of Both SDA and SCL
Signals
tF
(Note 13)
20 +
0.1CB
300
ns
Setup Time for STOP Condition
tSU:STO
0.6
F
s
Capacitive Load for each Bus
Line
CB
(Note 13)
400
pF
SCL Spike Suppression
tSP
60
ns
Oscillator Stop Flag (OSF) Delay
tOSF
(Note 14)
100
ms
Timeout Interval
tTIMEOUT (Note 15)
25
35
ms