EasyManuals Logo

Texas Instruments CC2500 User Manual

Texas Instruments CC2500
96 pages
To Next Page IconTo Next Page
To Next Page IconTo Next Page
To Previous Page IconTo Previous Page
To Previous Page IconTo Previous Page
Page #18 background imageLoading...
Page #18 background image
CC2500
S
WRS040
C
Page
18
of
89
balun that converts the differential RF signal
on
CC2500
to a single
-
ended RF signal.
C121
and C131
are needed for DC
blocking
.
Together with an appropriate LC network, the
balun components also transform the
impedance to match a 50
antenna (or
cable). Suggested values are listed in
Table
15
.
The balun and LC filter component v
alues and
their placement are important to keep the
performance optimized. It is
highly
recommended to follow the CC2500EM
refer
ence design
(
[4]
)
.
Crystal
The crystal oscillator uses an external crystal
with two
loading capacitors (C81 and C101).
See Section
26
on page
50
for details.
Power
Supply D
ecoupling
The power supply must be properly decoupled
close to the supply pins. Note that de
coupling
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.
The
CC2500EM
reference design
(
[4]
)
sh
ould be
followed closely.
Component
Description
C51
Decoupling capacitor for on
-
chip voltage regulator to digital part
C81/C101
Crystal loading capacitors, see Section
26
on page
50
for details
C121/C131
RF balun DC blocking capacitors
C122/C132
RF balun/matching capacitors
C123/C124
RF LC filter/matching capacitors
L121/L131
RF balun/matching inductors (inexpensive multi
-
layer type)
L122
RF LC filter inductor (inexpensiv
e multi
-
layer type)
R171
Resistor for internal bias current reference
XTAL
26
-
27 MHz crystal, see Section
26
on page
50
for details
Table
14
: Overview of
E
xternal
C
omponents (excluding supply decoupling capacitors)
Antenna
(50 Ohm)
Digital Inteface
1.8V-3.6V power supply
6 GDO0
7 CSn
8 XOSC_Q1
9 AVDD
10 XOSC_Q2
SI 20
GND 19
DGUARD 18
RBIAS 17
GND 16
1 SCLK
2 SO (GDO1)
3 GDO2
4 DVDD
5 DCOUPL
AVDD 15
AVDD 14
RF_N 13
RF_P 12
AVDD 11
XTAL
C122
C132
L131
L121
L122
C123
C124
R171
C81
C101
C51
CSn
GDO0
(optional)
GDO2
(optional)
SO
(GDO1)
SCLK
SI
CC2500
DIE ATTACH PAD:
C131
C121
Alternative:
Folded dipole PCB
antenna (no external
components needed)
Figure
3
: Typical
A
pplication and
E
valuation
C
ircuit (
excluding supply decoupling capacitors
)

Table of Contents

Questions and Answers:

Question and Answer IconNeed help?

Do you have a question about the Texas Instruments CC2500 and is the answer not in the manual?

Texas Instruments CC2500 Specifications

General IconGeneral
BrandTexas Instruments
ModelCC2500
CategoryTransceiver
LanguageEnglish

Related product manuals