CC1070 Datasheet, PDF (34/57 Pages) Texas Instruments – Single Chip Low Power RF Transmitter for Narrowband Systems

CC1070
Power Down mode
Turn on crystal oscillator core
MAIN: PD_MODE=1, FS_PD=1,
XOSC_PD=0, BIAS_PD=1
PA_POWER: 00h
Wait 1.2 ms*
Turn on bias generator
MAIN: BIAS_PD = 0
Wait 150 µs
Turn on frequency synthesizer
MAIN: F_REG=1, FS_PD=0
Wait until lock is detected from LOCK
pin or STATUS register
Turn on TX:
MAIN: PD_MODE = 0
Wait 100 µs then set PA_POWER
*Time to wait depends
on the crystal frequency
and the load capacitance
TX mode
Set PA_POWER = 00h
Wait 100 µs
Turn off TX:
MAIN: PD_MODE = 1, FS_PD=1,
XOSC_PD=1, BIAS_PD=1
Power Down mode
Figure 19. Sequence for activating TX mode
17 Crystal Oscillator
Any crystal frequency in the range 4 - 20
MHz can be used. The crystal frequency is
used as reference for the data rate (as
well as other internal functions) and in the
4 – 20 MHz range the frequencies 4.9152,
7.3728, 9.8304, 12.2880, 14.7456,
17.2032, 19.6608 MHz will give accurate
data rates as shown in Table 14. The
crystal frequency will influence the
SWRS043
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