AN2262 Motorola / Freescale Semiconductor, AN2262 Datasheet - Page 15

• Manufacturer Part Number: AN2262
• Description: Wireless HC08 Modem
• Manufacturer: Motorola / Freescale Semiconductor

RF Chip Set MC33491/MC33493/MC33591/3 and RF Protocol
RF Circuitry
MC33491/MC33493
Transmitter
MOTOROLA
This section provides information on the RF chip set and protocol.
In this application 868-MHz RF chips are used. MC33491 (code name
Tango II) is used as an ASK transmitter, MC33591/3 (code name Romeo II) is
a complementary ASK receiver. The two are paired for seamless operation in
the European (868 MHz) or US (915 MHz) unlicensed bands. The chips are
ultra low-cost, highly integrated components originally targeted for remote
keyless car entry applications.
The MC33491/MC33493 transmitter uses the configuration shown in
Besides two decoupling capacitors (C3 and C9) only minimum components are
required:
•
•
•
•
•
Quartz (X2) and the required capacitor (C4)
An impedance matching inductor (L1)
An RF path DC decoupling capacitor (C5)
A choke (L2) to bias output stage
A resistor (R7) controls the output power
Figure 6. MC33491/MC33493 Application Schematic
Wireless HC08 Modem
RF Chip Set MC33491/MC33493/MC33591/3 and RF Protocol
Figure
AN2262/D
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6.