Texas Instruments 2000 LF Series, Примечание к применению

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Lit Number: 11-06-21-068
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Figure 8. RFM-008B RF Module and ACC-008A Tuning Board
The board has a wide range of capacitance, which can be selected using on-board
jumpers. This arrangement allows for antennas with inductances from 12 to 80 µH to
be connected and fine tuned by a variable inductor.
3.1.4 The STU-MRD1 MicroReader.
This reader is shown in Figure 9.
Figure 9. The MicroReader
Unlike the other RF modules already described which need high Q antennas for
optimum performance; the MicroReader is designed for low Q antennas. Antenna Q
is described in more detail in later sections but in general, low Q antennas are more
tolerant of miss-tuning and the presence of metal. If MicroReader antennas have an
inductance close to 47 µH, then fine tuning is rarely necessary.
4 Antenna Design
Making antennas for S2000 Series readers is straight-forward. Only two
characteristics need to be controlled - Inductance and antenna Q