Unless otherwise noted, these specifications apply for V

T

Parameter

Conditions

Typical

Limits

Units

(Note 6)

(Note 7)

(Limit)

Local and Remote T_CRIT Default

Temperature Setting

(Note 11)

+85

˚C

Logic Electrical Characteristics

DIGITAL DC CHARACTERISTICS

Unless otherwise noted, these specifications apply for V

T

Symbol

Parameter

Conditions

Typical

Limits

Units

(Note 6)

(Note 7)

(Limit)

SMBData, SMBCLK INPUTS

V

IN(1)

Logical “1” Input Voltage

2.1

V (min)

V

IN(0)

Logical “0”Input Voltage

0.8

V (max)

V

IN(HYST)

SMBData and SMBCLK Digital

Input Hysteresis

400

mV

I

IN(1)

Logical “1” Input Current

V

0.005

µA (max)

I

IN(0)

Logical “0” Input Current

V

−0.005

µA (max)

C

IN

Input Capacitance

5

pF

ALL DIGITAL OUTPUTS

I

OH

High Level Output Current

V

10

µA (max)

V

OL

SMBus Low Level Output Voltage

I

I

0.4

0.6

V (max)

SMBus DIGITAL SWITCHING CHARACTERISTICS

Unless otherwise noted, these specifications apply for V

pF. Boldface limits apply for T

The switching characteristics of the LM90 fully meet or exceed the published specifications of the SMBus version 2.0. The fol-

lowing parameters are the timing relationships between SMBCLK and SMBData signals related to the LM90. They adhere to

but are not necessarily the 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

from V

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

SMBData 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

900

ns (min)

ns (max)

t

HD;STA

Start Condition SMBData Low to SMBCLK

Low (Start condition hold before the first

clock falling edge)

100

ns (min)

t

SU;STO

Stop Condition SMBCLK High to SMBData

Low (Stop Condition Setup)

100

ns (min)

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