CC1150 Datasheet, PDF (10/50 Pages) Texas Instruments – Single Chip Low Cost Low Power RF-Transmitter

CC1150
reference frequency for the synthesizer, as
well as clocks for the digital part.
A 4-wire SPI serial interface is used for
configuration and data buffer access.
14 Application Circuit
Only a few external components are required
for using the . CC1150 The recommended
application circuit is shown in Figure 3. The
external components are described in Table
12, and typical values are given in Table 13.
Bias resistor
The bias resistor R141 is used to set an
accurate bias current.
Balun and RF matching
C101, C111, L101 and L111 form a balun that
converts the differential RF port on CC1150 to a
single-ended RF signal (C104 is also needed
for DC blocking). Together with an appropriate
LC network, the balun components also
transform the impedance to match a 50Ω
antenna (or cable). Component values for the
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Suggested values for 315MHz, 433MHz and
868/915MHz are listed in Table 13.
The digital baseband includes support for
channel configuration, packet handling and
data buffering.
Crystal
The crystal oscillator uses an external crystal
with two loading capacitors (C51 and C71).
See section 29 on page 27 for details.
Additional filtering
Additional external components (e.g. an RF
SAW filter) may be used in order to improve
the performance in specific applications.
Power supply decoupling
The power supply must be properly decoupled
close to the supply pins. Note that decoupling
capacitors are not shown in the application
circuit. The placement and the size of the
decoupling capacitors are very important to
achieve the optimum performance. Chipcon
provides a reference design that should be
followed closely.
Component
C41
C51/C71
C101/C111
C102/C103
C104
C105
L101/L111
L102/L103
R141
XTAL
Description
100nF decoupling capacitor for on-chip voltage regulator to digital part
Crystal loading capacitors, see section 29 on page 27 for details
RF balun/matching capacitors
RF LC filter/matching capacitors
RF balun DC blocking capacitor
RF LC filter DC blocking capacitor (only needed if there is a DC path in the antenna)
RF balun/matching inductors (inexpensive multi-layer type)
RF LC filter/matching inductor (inexpensive multi-layer type)
56kΩ resistor for internal bias current reference
26MHz-27MHz crystal, see section 29 on page 27 for details
Table 12: Overview of external components (excluding supply decoupling capacitors)
Preliminary Data Sheet (rev. 1.0.) SWRS037
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