Logic Electrical Characteristics

DIGITAL DC CHARACTERISTICS

Unless otherwise noted, these specifications apply for V

T

Symbol

Parameter

Conditions

Typical

LM91D

Units

(Note 6)

Limits

(Note 7)

(Limit)

SMBData, SMBCLK

V

IN(1)

Logical “1” Input Voltage

2.1

V (min)

V

IN(0)

Logical “0”Input Voltage

0.8

V (max)

I

IN(1)

Logical “1” Input Current

V

0.005

1.0

µA (max)

I

IN(0)

Logical “0” Input Current

V

−0.005

−1.0

µA (max)

ADD0, ADD1

V

IN(1)

Logical “1” Input Voltage

V

CC

1.6

V (min)

V

IN(0)

Logical “0”Input Voltage

GND

0.5

V (max)

I

IN(1)

Logical “1” Input Current

V

50

600

µA (max)

I

IN(0)

Logical “0” Input Current

V

50

600

µA (max)

ALL DIGITAL INPUTS

C

IN

Input Capacitance

20

pF

ALL DIGITAL OUTPUTS

I

OH

High Level Output Current

V

100

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 LM91 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 LM91. 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 12)

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)

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