AC Electrical Characteristics

The following specifications apply for +2.8 V

DC

face limits apply for T

Symbol

Parameter

Conditions

Typical

Limits

Units

(Note 9)

(Note 10)

(Limits)

SERIAL BUS TIMING CHARACTERISTICS

t

1

SMBCLK (Clock) Period

2.5

µs (min)

t

rise

SMBCLK and SMBData Rise Time

1

µs (max)

t

fall

SMBCLK and SMBData Fall Time

300

ns (max)

t

2

Data In Setup Time to SMBCLK High

100

ns (min)

t

3

Data Out Stable After SMBCLK Low

100

ns (min)

300

ns (max)

t

4

SMBData Low Setup Time to SMBCLK Low

(start)

100

ns (min)

t

5

SMBData High Hold Time After SMBCLK

High (stop)

100

ns (min)

t

TIMEOUT

SMBCLK low time required to reset the Serial

Bus Interface to the Idle State

31

25

35

ms

ms (min)

ms (max)

C

L

Capacitive Load on SMBCLK and SMBData

80

pF (max)

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is

functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed

specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed test

conditions.

Note 2: All voltages are measured with respect to GND, unless otherwise specified.

Note 3: The Absolute maximum input range for :

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.

Note 6: The human body model is a 100 pF capacitor discharged through a 1.5 k

Ω resistor into each pin.

Note 7: See the section titled “Surface Mount” found in any post 1986 National Semiconductor Linear Data Book for other methods of soldering surface mount

devices.

Note 8: Parasitics and or ESD protection circuitry are shown in the figure below for the LM87’s pins. The nominal breakdown voltage of the zener D3 is 6.5 V. Care

should be taken not to forward bias the parasitic diode, D1, present on pins: A0/NTEST_OUT, A1 and DACOut/NTEST_IN. Doing so by more than 50 mV may corrupt

a temperature or voltage measurement.

10099504

FIGURE 1. Serial Bus Timing Diagram

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