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BEST

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SN74CB3T3245

www.ti.com

SCDS136B – OCTOBER 2003 – REVISED JUNE 2015

Typical Application (continued)

9.2.3 Application Curves

Figure 9. Data Output Voltage vs Data Input Voltage

Figure 10. Data Output Voltage vs Data Input Voltage

10 Power Supply Recommendations

The power supply can be any voltage between the minimum and maximum supply voltage rating located in the

Recommended Operating Conditions.

supply, a 0.1-

0.022-

capacitor is recommended for each supply pin. It is acceptable to parallel multiple bypass capacitors to reject

different frequencies of noise. 0.1-

μF and 1-μF capacitors are commonly used in parallel. The bypass capacitor

should be installed as close to the power terminal as possible for best results.

11 Layout

11.1 Layout Guidelines

Reflections and matching are closely related to the loop antenna theory but are different enough to be discussed

separately from the theory. When a PCB trace turns a corner at a 90° angle, a reflection can occur. A reflection

occurs primarily because of the change of width of the trace. At the apex of the turn, the trace width increases to

1.414 times the width. This increase upsets the transmission-line characteristics, especially the distributed

capacitance and self–inductance of the trace which results in the reflection. Not all PCB traces can be straight

and therefore some traces must turn corners. Figure 11 shows progressively better techniques of rounding

corners. Only the last example (BEST) maintains constant trace width and minimizes reflections.

11.2 Layout Example

Figure 11. Trace Example

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