AN2719 Freescale Semiconductor / Motorola, AN2719 Datasheet - Page 8

• Manufacturer Part Number: AN2719
• Description: A Transmitter Using Tango3 (Step-by-step Design for ISM Bands)
• Manufacturer: Freescale Semiconductor / Motorola

Tango3 RF Module
We chose L1 = 100 nH as the maximum inductance value on the circuit to avoid any effect the parallel
resonance of the various coils, and to comply with commonly available values for 0603 inductors.
This gives:
This matching network also helps attenuate signal harmonics, as can be seen in the simulation in
Figure
8
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6. The attenuation at 866 MHz (second harmonic of 433 MHz) is about 40dB.
L1 = 100 nH
C4 = 100 pF
C8 = 6.8 pF
L2 = 27 nH
C9 = 27 pF
L3 = 12 nH
C10 = 22 pF
Figure 5. Matching Network and Simple Smith Chart
A Transmitter Using Tango3, Rev. 0
Freescale Semiconductor