CC2510FX Datasheet, PDF (207/244 Pages) List of Unclassifed Manufacturers – True System-on-Chip with Low Power RF Transceiver and 8051 MCU

C2510Fx / CC2511Fx
The base or start frequency is set by the 24 bit
frequency word located in the FREQ2, FREQ1
and FREQ0 registers. This word will typically
be set to the centre of the lowest channel
frequency that is to be used.
The desired channel number is programmed
with the 8-bit channel number register,
CHANNR.CHAN, which is multiplied by the
channel offset. The resultant carrier frequency
is given by:
( ( )) f_carrier
=
f _ref
2¹⁶
⋅
FREQ + CHAN
⋅
(256 + CHANSPC
_ M ) ⋅ 2^{CHANSPC _ E−2}
With a reference frequency, f_Ref, equal to 26
MHz, the maximum channel spacing is 405
kHz. To get e.g. 1 MHz channel spacing one
solution is to use 333 kHz channel spacing
and select each third channel in
CHANNR.CHAN.
The preferred IF frequency is programmed
with the FSCTRL1.FREQ_IF register. The IF
frequency is given by:
f _IF
=
f _ref
2¹⁰
⋅ FREQ _ IF
Note that the SmartRF^® Studio software [8]
automatically calculates the optimum register
setting based on channel spacing and channel
filter bandwidth.
If any frequency programming register is
altered when the frequency synthesizer is
running, the synthesizer may give an
undesired response. Hence, the frequency
programming should only be updated when
the radio is in the IDLE state.
14.14 VCO
The VCO is completely integrated on-chip.
14.14.1 VCO and PLL Self-Calibration
The VCO characteristics will vary with
temperature and supply voltage changes, as
well as the desired operating frequency. In
order to ensure reliable operation,
CC2510Fx/CC2511Fx includes frequency
synthesizer self-calibration circuitry. This
calibration should be done regularly, and must
be performed after turning on power and
before using a new frequency (or channel).
The number of f_Ref periods for completing the
PLL calibration is given in Table 71 on Page
205.
14.15 Output Power Programming
The RF output power level from the device is
programmed through the PA_TABLE0 register.
Table 72 contains recommended PA_TABLE0
The calibration can be initiated automatically or
manually. The synthesizer can be
automatically calibrated each time the
synthesizer is turned on, or each time the
synthesizer is turned off automatically. This is
configured with the MCSM0.FS_AUTOCAL
register setting. In manual mode, the
calibration is initiated when the SCAL
command strobe is activated in the IDLE
mode.
Note that the calibration values are maintained
in power-down modes PM1/2/3, so the
calibration is still valid after waking up from
these power-down modes (unless supply
voltage or temperature has changed
significantly).
settings for various output levels and
frequency bands, together with current
consumption in the RF transceiver.
SWRS055D
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