Voltage Regulators; Output Power Programming - Texas Instruments CC2500 TK Manual

23 Voltage Regulators

CC2500 contains several on-chip linear voltage
regulators, which generate the supply voltage
needed by low-voltage
voltage regulators are invisible to the user, and
can be viewed as integral parts of the various
modules. The user must however make sure
that the absolute maximum ratings and
required pin voltages in Table 1 and Table 13
are not exceeded. The voltage regulator for
the digital core requires
decoupling capacitor.
Setting the CSn pin low turns on the voltage
regulator to the digital core and starts the
crystal oscillator. The SO pin on the SPI
interface must go low before the first positive
edge of SCLK (setup time is given in Table
16).

24 Output Power Programming

The RF output power level from the device has
two levels of programmability, as illustrated in
Figure 21.
The RF output power level from the device is
programmed through the PATABLE register.

If 2-FSK, GFSK or MSK modulation is
used the desired
programmed to index 0 in the PATABLE
register (PATABLE(0)[7:0]). The 3-bit
FREND0.PA_POWER value shall be set to 0
(reset default value).

If OOK modulation is used the desired
output power for the logic 0 and logic 1
power levels are programmed to index 0
and index 1 in the PATABLE
respectively (PATABLE(0)[7:0]
PATABLE(1)[7:0]).
modules. These
one external
output power is
register
and
The 3-bit
SWRS040C
If the chip is programmed to enter power-down
mode, (SPWD strobe issued), the power will be
turned off after CSn goes high. The power and
crystal oscillator will be turned on again when
CSn goes low.
The voltage regulator output should only be
used for driving the CC2500 .
FREND0.PA_POWER value shall be set to
1.
Table 31 contains recommended PATABLE
settings for various
frequency bands. See Section 10.6 on page
24 for PATABLE programming details. The

SmartRF Studio software [5] should be used
to obtain optimum PATABLE settings for
various output powers.
PATABLE must be programmed in burst mode
if writing to other entries than PATABLE(0)
(OOK modulation). Note that all content of the
PATABLE, except for the first byte (index 0) is
lost when entering the SLEEP state.
CC2500
output levels and
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