Datasheet
Logic Electrical Characteristics (Continued)
SMBus DIGITAL SWITCHING CHARACTERISTICS
Unless otherwise noted, these specifications apply for V
CC
=+3.0 Vdc to +3.6 Vdc, C
L
(load capacitance) on output lines = 80
pF. Boldface limits apply for T
A
=T
J
=T
MIN
to T
MAX
; all other limits T
A
=T
J
= +25˚C, unless otherwise noted.
The switching characteristics of the LM83 fully meet or exceed the published specifications of the SMBus or I
2
C bus. The fol-
lowing parameters are the timing relationships between SMBCLK and SMBData signals related to the LM83. They are not the
I
2
C or SMBus bus specifications.
Symbol Parameter Conditions Typical Limits Units
(Note 6) (Note 7) (Limit)
f
SMB
SMBus Clock Frequency 100
10
kHz (max)
kHz (min)
t
LOW
SMBus Clock Low Time 10 % to 10 % 1.3
25
µs (min)
ms (max)
t
LOW
MEXT Cumulative Clock Low Extend Time 10 ms (max)
t
HIGH
SMBus Clock High Time 90 % to 90% 0.6 µs (min)
t
R,SMB
SMBus Rise Time 10% to 90% 1 µs (max)
t
F,SMB
SMBus Fall Time 90% to 10% 0.3 ns (max)
t
OF
Output Fall Time C
L
= 400 pF,
I
O
=3mA
250 ns (max)
t
TIMEOUT
SMBData and SMBCLK Time Low for
Reset of Serial Interface (Note 12)
25
40
ms (min)
ms (max)
t
1
SMBCLK (Clock) Period 10 µs (min)
t
2
,
t
SU;DAT
Data In Setup Time to SMBCLK High 100 ns (min)
t
3
,
t
HD;DAT
Data Out Stable after SMBCLK Low 300
TBD
ns (min)
ns (max)
t
4
,
t
HD;STA
SMBData Low Setup Time to SMBCLK
Low
100 ns (min)
t
5
,
t
SU;STO
SMBData High Delay Time after
SMBCLK High (Stop Condition Setup)
100 ns (min)
t
6
,
t
SU;STA
SMBus Start-Condition Setup Time 0.6 µs (min)
t
BUF
SMBus Free Time 1.3 µs (min)
SMBus Communication
DS101058-4
LM83
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