SMBus Digital Switching Characteristics

Unless otherwise noted, these specifications apply for V

80 pF. Boldface limits apply for T

switching characteristics of the LM95235 fully meet or exceed the published specifications of the SMBus version 2.0. The fol-

lowing parameters are the timing relationships between SMBCLK and SMBDAT signals related to the LM95235. They adhere

to, but are not necessarily, the SMBus 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

from V

4.7

25

µs (min)

ms (max)

t

HIGH

SMBus Clock High Time

from V

4.0

µs (min)

t

R,SMB

SMBus Rise Time

(Note 12)

1

µs (max)

t

F,SMB

SMBus Fall Time

(Note 13)

0.3

µs (max)

t

OF

Output Fall Time

C

I

250

ns (max)

t

TIMEOUT

SMBDAT and SMBCLK Time Low for Reset

of Serial Interface (Note 14)

25

35

ms (min)

ms (max)

t

SU;DAT

Data In Setup Time to SMBCLK High

250

ns (min)

t

HD;DAT

Data Out Stable after SMBCLK Low

300

1075

ns (min)

ns (max)

t

HD;STA

Start Condition SMBDAT Low to SMBCLK

Low (Start condition hold before the first

clock falling edge)

100

ns (min)

t

SU;STO

Stop Condition SMBCLK High to SMBDAT

Low (Stop Condition Setup)

100

ns (min)

t

SU;STA

SMBus Repeated Start-Condition Setup

Time, SMBCLK High to SMBDAT Low

0.6

µs (min)

t

BUF

SMBus Free Time Between Stop and Start

Conditions

1.3

µs (min)

SMBus Communication

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