Page 345 - Complete Wireless Design
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Support Circuit Design
344 Chapter Eight
Figure 8.10 A switch for DC
using a transistor.
Figure 8.11 An RF switch using a diode.
Small-signal very high isolation PIN SPDT switch (Fig. 8.12). This switch can be
designed with the following formulas, but requires both a forward and a
reverse-bias voltage to turn ON and OFF.
1. RFC 500 ohms (X ) at f .
L r
2. C C 1 ohm (X ) at f .
B C C r
DC bias 0.9
3. R ≈
50 mA
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