CC1021_12 Datasheet, PDF (56/94 Pages) Texas Instruments – Single Chip Low Power RF Transceiver for Narrowband Systems

CC1021
Power Down mode
*Time to wait depends
on the crystal frequency
and the load capacitance
Turn on crystal oscillator core
MAIN: PD_MODE=1, FS_PD=1, XOSC_PD=0, BIAS_PD=1
Wait 1.2 ms*
Turn on bias generator. MAIN: BIAS_PD=0
Wait 150 us
RX
TX
RX or TX?
Turn on frequency synthesizer
MAIN: RXTX=0, F_REG=0, FS_PD=0
Turn on frequency synthesizer
MAIN: RXTX=1, F_REG=1, FS_PD=0
Wait until lock detected from LOCK pin
or STATUS register
Turn on RX: MAIN: PD_MODE = 0
Wait until lock detected from LOCK pin
or STATUS register
Turn on TX: MAIN: PD_MODE = 0
Set PA_POWER
RX mode
TX mode
Turn off RX/TX:
MAIN: PD_MODE = 1, FS_PD=1,
XOSC_PD=1, BIAS_PD=1
PA_POWER=00h
Power Down mode
Figure 31. Sequence for activating RX or TX mode
18. On-Off Keying (OOK)
The data modulator can also provide OOK
(On-Off Keying) modulation. OOK is an
ASK (Amplitude Shift Keying) modulation
using 100% modulation depth. OOK
modulation is enabled in RX and in TX by
setting TXDEV_M[3:0] = 0000 in the
DEVIATION register. An OOK eye
diagram is shown in Figure 32.
The data demodulator can also perform
OOK demodulation. The demodulation is
done by comparing the signal level with
SWRS045C
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