Rainbow Electronics LM84 - Manual (Page 15)

3.0 Application Hints
(Continued)
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
CC
and
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
LM84
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