7.

The ideal place to connect the LM84’s GND pin is as

close as possible to the Processors GND associated

with the sense diode. For the Pentium II this would be

pin A14.

Noise on the digital lines, overshoot greater than V

undershoot less than GND, may prevent successful SMBus

communication with the LM84. SMBus no acknowledge is

the most common symptom, causing unnecessary traffic on

the bus. Although, the SMBus maximum frequency of com-

munication is rather low (400 kHz max) care still needs to be

taken to ensure proper termination within a system with

multiple parts on the bus and long printed circuit board

traces.

4.0 Typical Applications

DS100961-15

FIGURE 6. Recommended Diode Trace Layout

DS100961-17

Using a Diode Connected 2N3904 as a Remote Temperture Sensing Element

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