LM82
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 LM82 fully meet or exceed the published specifications of the SMBus or I
2
C bus. The following param-
eters are the timing relationships between SMBCLK and SMBData signals related to the LM82. They are not the I
2
C or SMBus
bus specifications.
Symbol
f
SMB
t
LOW
Parameter
SMBus Clock Frequency
SMBus Clock Low Time
10 % to 10 %
Conditions
Typical
Limits
100
10
1.3
25
10
90 % to 90%
10% to 90%
90% to 10%
C
L
= 400 pF,
I
O
= 3 mA
1
0.3
250
25
40
10
100
300
TBD
100
100
0.6
1.3
SMBus Communication
0.6
Units
(Limit)
kHz (max)
kHz (min)
µs (min)
ms (max)
ms (max)
µs (min)
µs (max)
ns (max)
ns (max)
ms (min)
ms (max)
µs (min)
ns (min)
ns (min)
ns (max)
ns (min)
ns (min)
µs (min)
µs (min)
t
LOW
MEXT Cumulative Clock Low Extend Time
t
HIGH
t
R,SMB
t
F,SMB
t
OF
t
TIMEOUT
t
1
t
2
,
t
SU;DAT
t
3
,
t
HD;DAT
t
4
,
t
HD;STA
t
5
,
t
SU;STO
t
6
,
t
SU;STA
t
BUF
SMBus Clock High Time
SMBus Rise Time
SMBus Fall Time
Output Fall Time
SMBData and SMBCLK Time Low for
Reset of Serial Interface (Note 12)
SMBCLK (Clock) Period
Data In Setup Time to SMBCLK High
Data Out Stable after SMBCLK Low
SMBData Low Setup Time to SMBCLK
Low
SMBData High Delay Time after SMBCLK
High (Stop Condition Setup)
SMBus Start-Condition Setup Time
SMBus Free Time
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