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)

t

BUF

SMBus Free Time

1.3

µs (min)

SMBus Communication

20034304

SMBus TIMEOUT

20034313

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications do not apply when operating

the device beyond its rated operating conditions.

maximum package input current rating limits the number of pins that can safely exceed the power supplies with an input current of 5 mA to four.

Parasitics and or ESD protection circuitry are shown in the figure below for the LM91’s pins. The nominal breakdown voltage of the zener D3 is 6.5V. Care should

be taken not to forward bias the parasitic diode, D1, present on pins: NC pins 1,5 and 9, D+, ADD1 and ADD0. Doing so by more than 50 mV may corrupt a

temperature or voltage measurement.

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