SMBus DIGITAL SWITCHING CHARACTERISTICS

Unless otherwise noted, these specifications apply for V

pF. Boldface limits apply for T

characteristics of the LM82 fully meet or exceed the published specifications of the SMBus or I

eters are the timing relationships between SMBCLK and SMBData signals related to the LM82. They are not the I

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

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

I

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

t

SU;DAT

Data In Setup Time to SMBCLK High

100

ns (min)

t

t

HD;DAT

Data Out Stable after SMBCLK Low

300

TBD

ns (min)

ns (max)

t

t

HD;STA

SMBData Low Setup Time to SMBCLK

Low

100

ns (min)

t

t

SU;STO

SMBData High Delay Time after SMBCLK

High (Stop Condition Setup)

100

ns (min)

t

t

SU;STA

SMBus Start-Condition Setup Time

0.6

µs (min)

t

BUF

SMBus Free Time

1.3

µs (min)

SMBus Communication

10129704

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