Rainbow Electronics DS1375 - Manual (Page 3)

DS1375
2-Wire Digital Input RTC with Alarm
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Note 8: After this period, the first clock pulse is generated.
Note 9: A device must internally provide a hold time of at least 300ns for the SDA signal (see the V IHMIN of the SCL signal) to
bridge the undefined region of the falling edge of SCL.
Note 10: The maximum t HD:DAT is only met if the device does not stretch the low period (t LOW ) of the SCL signal.
Note 11: A fast-mode device can be used in a standard-mode system, but the requirement t SU:DAT
≥ 250ns must then be met.
This is automatically the case if the device does not stretch the low period of the SCL signal. If such a device does
stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line t
R MAX
+ t
SU:DAT
= 1000 + 250
= 1250ns before the SCL line is released.
Note 12: C B —total capacitance of one bus line in pF.
AC ELECTRICAL CHARACTERISTICS
(V CC = V CCMIN to V CCMAX , T A = -40°C to +85°C, unless otherwise noted.) (Note 1, Figure 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Fast mode 100 400
SCL Clock Frequency f SCL
Standard mode 0 100
kHz
Fast mode 1.3 Bus Free Time Between STOP
and START Conditions
t BUF
Standard mode 4.7
µs
Fast mode 0.6 Hold Time (Repeated) START
Condition (Note 8)
t HD:STA
Standard mode 4.0
µs
Fast mode 1.3
Low Period of SCL Clock t
LOW
Standard mode 4.7
µs
Fast mode 0.6
High Period of SCL Clock t HIGH
Standard mode 4.0
µs
Fast mode 0 0.9
Data Hold Time (Notes 9, 10) t HD:DAT
Standard mode 0 0.9
µs
Fast mode 100
Data Setup Time (Note 11) t SU:DAT
Standard mode 250
ns
Fast mode 0.6
Start Setup Time t
SU:STA
Standard mode 4.7
µs
Fast mode 300 Rise Time of Both SDA and SCL
Signals (Note 12)
t R
Standard mode
20 + 0.1C B
1000
ns
Fast mode 300 Fall Time of Both SDA and SCL
Signals (Note 12)
t
F
Standard mode
20 + 0.1C
B
300
ns
Fast mode 0.6
Setup Time for STOP Condition t SU:STO
Standard mode 4.7
µs
Capacitive Load for Each Bus
Line (Note 12)
C B 400 pF
Pulse Width of Spikes that Must
be Suppressed by the Input Filter
t SP Fast mode 30 ns