CC1010PAGR Datasheet, PDF (85/149 Pages) Texas Instruments – Single Chip Very Low Power RF Transceiver with 8051-Compatible Microcontroller

CC1010
17.3 RF Application Circuit
Very few external components are
required for operation of the RF
transceiver. A typical application circuit is
shown in Figure 20. Component values are
shown in Table 28.
17.3.1 Input / output matching
C31/L32 is the input match for the
receiver, and L32 is also used as a DC
choke for biasing. C41, L41 and C42 are
used to match the transmitter to a 50-Ohm
load. An internal T/R switch circuit makes
it possible to connect the input and output
together and match the transceiver to 50
Ω in both RX and TX mode. See the Input
/ Output Matching section on page 126 for
details.
17.3.2 VCO inductor
The VCO is completely integrated except
for the inductor L101.
Component values for the matching
network and VCO inductor are easily
calculated using the SmartRF^® Studio
software for any operation frequency.
17.3.3 Additional filtering
Additional external components (e.g. RF
LC or SAW-filter) may be used in order to
improve the performance in specific
applications. See also the Optional LC
Filter section on page 128 for further
information. If a SAW filter is used, it
should be included in the RX path only (an
external RX/TX switch should then be
used).
17.3.4 Voltage supply decoupling
Voltage supply filtering and de-coupling
capacitors must be used (not shown in the
application circuit). These capacitors
should be placed as close as possible to
the voltage supply pins of CC1010.
The placement and size of the decoupling
capacitors and power supply filtering are
very important to achieve the best
sensitivity and lowest possible LO leakage
and the reference layouts should be
followed.
SWRS047A
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