Texas Instruments 2000 LF Series, Примечание к применению

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Lit Number: 11-06-21-068
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Not shown in Figure 19 is the stick antenna (RI-ANT-S01C). This
antenna does not have a long range but because of its small area,
it picks up much less ambient noise and is often used below roller
conveyor systems.
4.4.1 Antenna Size vs. Inductance
There is no such thing as ‘half a turn’ when constructing multi-winding antennas, so
although you may require a particular sized antenna, you could have to compromise
on shape. The dimensions of Texas Instrument’s own standard antennas are dictated
by the number of windings required to achieve an inductance of 27 µH.
Figure 20. Windings Vs. Inductance
If we consider single turn loops, the approximate sizes to achieve 27 µH Inductance
are:
Figure 21. Single Loop Vs. 27 µH Inductance
G04E
G01E
G02E
G04E
3 TURNS
G01E
4 TURNS
G02E
7 TURNS
G04E
G01E
G02E
G04E
3 TURNS
G01E
4 TURNS
G02E
7 TURNS
1 TURN
2
3
4
4 m
1.25 m
0.64 m