MRF49XAT-I-ST Datasheet, PDF (62/102 Pages) Microchip Technology – ISM Band Sub-GHz RF Transceiver

MRF49XA
From PMCREG, the following points are applicable
when using the bit functionalities:
• The chip enters Receive mode if both the TXCEN
and RXCEN bits are set.
• FSK/DATA/FSEL input is equipped with an internal
pull-up resistor. To achieve minimum current
consumption, do not pull this input to logic low in
Sleep mode.
• To enable the RF synthesizer, the crystal oscillator
must be turned on.
• To turn on the baseband circuits, the RF
synthesizer and the crystal oscillator must be
enabled.
• Setting the RXCEN bit automatically turns on the
crystal oscillator, synthesizer, baseband circuits
and RF front end.
• Setting the TXCEN bit automatically turns on the
crystal oscillator, synthesizer and RF power
amplifier.
The clock tail and automatic crystal enable/disable
features help in reducing the power consumption and
are discussed in detail in Section 3.4, Crystal
Oscillator and Clock Output.
The registers associated with power management are:
• STSREG (see Register 2-1)
• GENCREG (see Register 2-2)
• RXCREG (see Register 2-7)
• PMCREG (see Register 2-13)
DS70590C-page 62
Preliminary
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