Noise on the digital lines, overshoot greater than V

undershoot less than GND, may prevent successful SMBus

communication with the LM91. 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

20034317

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

20034315

FIGURE 6. Recommended Diode Trace Layout

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