AN1833 Freescale Semiconductor / Motorola, AN1833 Datasheet - Page 18

• Manufacturer Part Number: AN1833
• Description: A Low-Power Wireless Remote Control Transmitter and Receiver
• Manufacturer: Freescale Semiconductor / Motorola

Application Note
Layout
and Practical
Considerations
18
The MC13176 is enabled by the MCU at pin 10 and data is input at
pin 16 creating the OOK modulation. At pins 1 and 4, an external
inductor is used as the resonator for the current controlled oscillator
(CCO). This RF resonator must be a high Q component and adjustable
to align the CCO to the reference source.
The application circuit uses a Coilcraft adjustable 7-mm shielded
inductor [10] (part number 150-04J08S).
Phase noise of the MC13176 measures at –85 dBc/Hz at 10-kHz
separation
system such as described in this application note.
These layout considerations are suggested:
In mixed signal applications, isolation of the digital and RF ground and
supply lines is a must. In addition, the receiver is properly shielded and
ac decoupled to eliminate interference by switching and high EMI/RFI
sources.
1. Use double sided PCB in which one side is the circuit side where
2. Keep all RF traces as short as possible.
3. Avoid point-to-point wiring; it is best to run the trace on the PCB.
4. Use controlled impedance microstrip lines in high frequency
5. Use ground return paths through ample size holes to the ground
6. Decouple V
Freescale Semiconductor, Inc.
For More Information On This Product,
all surface mounted components are placed and where the
interconnect and circuit traces are done; the other side is the V
ground side where leaded components are mounted and only a
few necessary circuit traces are done.
portions of the circuit.
side of the PCB.
board.
(Figure
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7). This offers ample performance for a wideband
where the pins of the IC contact the trace on the PC
MOTOROLA
AN1833
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