SMBus DIGITAL SWITCHING CHARACTERISTICS

Unless otherwise noted, these specifications apply for V

pF. Boldface limits apply for T

The switching characteristics of the LM84 fully meet or exceed the published specifications of the SMBus or I

lowing parameters are the timing relationships between SMBCLK and SMBData signals related to the LM84. They are not nec-

essarily the I

Symbol

Parameter

Conditions

Typical

Limits

Units

(Note 6)

(Note 7)

(Limit)

f

SMB

SMBus Clock Frequency

400

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

25

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

t

F;SMB

SMBus Fall Time

90% to 10%

0.3

µs

t

OF

Output Fall Time

C

I

250

ns (max)

t

TIMEOUT

SMBData and SMBCLK Time Low for

Reset of Serial Interface (Note 13)

25

40

ms (min)

ms (max)

t

1

SMBCLK (Clock) Period

2.5

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

0

0.9

ns (min)

µs (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

DS100961-4

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