DS3893AV datasheet(5/7 Pages) NSC

5 / 7 page

Switching Time Waveforms (Continued)

Typical Application

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Application Information

Due to the high current and very high speed capability of the

TURBOTRANSCEIVER’s driver output stage, circuit board

layout and bus grounding are critical factors that affect the

system performance.

Each of the TURBOTRANSCEIVER’s bus ground pins

should be connected to the nearest backplane ground pin

with the shortest possible path. The ground pins on the

connector should be distributed evenly through its length.

Although the bandgap reference receiver threshold provides

sufficient DC noise margin (Figure 9), ground noise and

ringing on the data paths could easily exceed this margin if

the series inductance of the traces and connectors are not

kept to a minimum. The bandgap ground pin should be

returned to the connector through a separate trace that does

not carry transient switching currents. The transceivers

should be mounted as close as possible to the connector. It

should be noted that even one inch of trace can add a

significant amount of ringing to the bus signal.

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FIGURE 7. Receiver Propagation Delay

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Note: tR =tF ≤ 4 ns From 10% to 90%

Note: n=1,2,3,4

FIGURE 8. Receiver Enable and Disable Times

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FIGURE 9. Noise Margin

DS3893AV Datasheet(PDF) 5 Page - National Semiconductor (TI)