Texas Instruments Chipcon CC2420DK User manual

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User Manual
Rev. 1.0
CC2420DK Development Kit
This datasheet has been downloaded fromhttp://www.digchip.com at this page

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Table of contents
INTRODUCTION ....................................................................................................................... 3
CC2420 EVALUATION MODULE ............................................................................................ 4
CIRCUIT DESCRIPTION .............................................................................................................. 4
PCB LAYOUT,CC2420EM....................................................................................................... 4
SCHEMATIC,CC2420EM ......................................................................................................... 8
BILL OF MATERIALS,CC2420EM .............................................................................................. 9
CC2400 EVALUATION BOARD............................................................................................. 10
POWER SUPPLY SECTION ........................................................................................................ 10
USB INTERFACE..................................................................................................................... 12
RS-232 INTERFACE................................................................................................................ 12
JUMPERS ............................................................................................................................... 12
MICROCONTROLLER AND FPGA.............................................................................................. 13
CONNECTORS ........................................................................................................................ 14
PCB LAYOUT,CC2400EB...................................................................................................... 15
SCHEMATICS,CC2400EB...................................................................................................... 18
BILL OF MATERIALS,CC2400EB ............................................................................................ 23
USING THE DEVELOPMENT KIT.......................................................................................... 29
CC2420 RF EVALUATION USING SMARTRF®STUDIO OR PACKET SNIFFER ............................... 29
USING THE CC2420DK FOR PROTOTYPING ............................................................................. 30
TROUBLESHOOTING ............................................................................................................ 31
IT DOES NOT WORK................................................................................................................. 31
SMARTRF®STUDIO DOES NOT RECOGNIZE THE CC2400EB .................................................... 31

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Introduction
The CC2420 is a true single-chip 2.4 GHz IEEE 802.15.4 compliant RF transceiver designed
for low-power and low-voltage wireless applications. The CC2420DK development kit is a
powerful and flexible tool specifically designed to make it easy for the user to evaluate the RF
performance of the CC2420 and to minimize the time spent on evaluation.
The Development Kit includes two CC2400EB Evaluation Boards and two CC2420EM
Evaluation Modules. The Evaluation Modules contain the CC2420 chip and required external
components.
The Evaluation Board serves as a motherboard for the Evaluation Modules. The Evaluation
Board provides a USB port, a serial port, buttons, LEDs, voltage regulator, configuration
jumpers and connectors to make it easy to interface the CC2420 with the SmartRF®Studio
software and various test equipment. The CC2400EB Evaluation Board is the same as for the
CC2400DK.
This User Manual describes how to use the Development Kit. SmartRF®Studio is
documented in its own user manual.
Your SmartRF®CC2420DK Development Kit should contain the following items:
Kit contents
Item Number of articles
Evaluation Board (CC2400EB) 2
Evaluation Module (CC2420EM) 2
Quick Start instructions 1
Antenna, 50Ωquarter-wave monopole, SMA male connector 2
SMA to BNC adapters 4
USB cable 2
CC2420 sample kit 1

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CC2420 Evaluation Module
The CC2420EM Evaluation Module contains the CC2420 chip together with the external
circuitry needed for proper operation. Not all components are needed in an actual application.
Please see the data sheet for a typical application circuit.
The CC2420 operates in the 2.4 GHz frequency band. Although this frequency band is
usually described as “world-wide”, some countries do not allow unlicensed operation in this
band.
Important: Contact your local telecommunication authorities before transmitting an RF signal.
Circuit description
The CC2420 RF section includes all the necessary components for correct operation.
The CC2420 is connected to a 16 MHz crystal.
The user can select between using the CC2420 on chip voltage regulator, or the regulator on
the CC2400EB. This is controlled by the jumper on CC2420EM. The default setting is to use
the CC2400EB regulator. If the internal regulator is selected, you must also change the
CC2400EB P12 jumper setting as given in figure 9.
The CC2420EM Evaluation Module can be plugged into the CC2400B Evaluation Board. Two
2x10 pin pin row connectors with 0.050-inch pitch are used for this purpose.
Figure 1: CC2420EM Evaluation Module
PCB layout, CC2420EM
RF circuits operating at high frequencies are sensitive to the physical layout of the PCB.
Chipcon has carefully optimized the layout of the CC2420EM Evaluation Module and we
therefore recommend that the user copies it when making own PCB designs.
The PCB is of a 4-layer type in order to provide a well-defined ground plane as well as
adequate routing space. The laminate used is standard FR-4 board material. The PCB is
1.0mm thick, with layer 1 on the top side, layers 2 and 3 are internal layers and layer 4 is on
the bottom side. Layers 1 and 4 are used for routing, and layer 3 is used for power routing. All
areas not utilized for routing are filled with copper connected to ground to provide RF
shielding. The ground planes on all layers are stitched together with closely spaced vias.

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Figure 2: CC2420EM PCB layout, layer 1
Figure 3: CC2420EM PCB layout, layer 2

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Figure 4: CC2420 PCB layout, layer 3
Figure 5: CC2420EM PCB layout, layer 4

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Figure 6a: CC2420EM component placement, top side
Figure 6b: CC2420EM component placement, bottom side

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Schematic, CC2420EM
Figure 7: CC2420EM schematic

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Bill of materials, CC2420EM
Bill of materials, CC2420EM
Reference Description Value Part
C1 Capacitor 0603 2.2 µF, 10% C_2U2_0603_X5R_K_10
C11 Capacitor 0402 100 nF, 10% C_100N_0402_X5R_J_10
C61 Capacitor 0402 0.5 pF, ± 0.25 pF C_0P5_0402_NP0_C_50
C62 Capacitor 0402 5.6 pF, ± 0.25 pF C_5P6_0402_NP0_C_50
C71 Capacitor 0402 5.6 pF, ± 0.25 pF C_5P6_0402_NP0_C_50
C81 Capacitor 0402 0.5 pF, ± 0.25 pF C_0P5_0402_NP0_C_50
C101 Capacitor 0402 10 nF, 10% C_10N_0402_X7R_K_25
C171 Capacitor 0402 68 pF, 5% C_68P_0402_NP0_J_50
C251 Capacitor 0402 100 nF, 10% C_100N_0402_X5R_K_10
C261 Capacitor 0402 100 nF, 10% C_100N_0402_X5R_K_10
C351 Capacitor 0402 100 nF, 10% C_100N_0402_X5R_K_10
C371 Capacitor 0402 68 pF, 5% C_68P_0402_NP0_J_50
C381 Capacitor 0402 22 pF, 5% C_22P_0402_NP0_J_50
C391 Capacitor 0402 22 pF, 5% C_22P_0402_NP0_J_50
C421 Capasitor 0805 10 uF, 15% C_10U_0805_X5R_L_25
C431 Capasitor 0805 10 uF, 15% C_10U_0805_X5R_L_25
C441 Capacitor 0402 68 pF, 5% C_68P_0402_NP0_J_50
L61 Inductor 0402 7.5 nH, 5% L_7N5_0402_J
L62 Inductor 0402 5.6 nH, 5% L_5N6_0402_J
L81 Inductor 0402 7.5 nH, 5% L_7N5_0402_J
P1 SMD pinrow socket SMD_SOCKET_2x10 (Samtec
SFM-110-02-S-D-A-K-TR)
P2 SMD pinrow socket SMD_SOCKET_2x10 (Samtec
SFM-110-02-S-D-A-K-TR)
P3 3 pin jumper 3 pin connector, 0.9 mm pin
P4 Surface-mount
SMA, straight
SMA_SMD
R1 Resistor 0603 0 ΩR_0_0603
R2 Resistor 0603 0 ΩR_0_0603
R421 Resistor 0402 2 Ω, 1% R2R0_0402_F
R451 Resistor 0402 43 kΩ, 1% R_43K_0402_F
U1 Single-chip
transceiver
CC2420
X1 Crystal, ceramic
SMD 4x25mm
X_16.000/10/10/10/16 (Toyocom
TSX-10A 16M 16pF)

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Note: The crystal X1 mounted on the EM board is a 16.000 MHz crystal, with ±10 ppm initial
tolerance, ± 10 ppm drift over temperature and a temperature range of -10˚C to +60˚C. The
crystal is designed for 16 pF load capacitance. In an actual application, the tolerance, drift
and temperature range of the crystal must be considered with application requirements in
mind. Please consult the data sheet and SmartRF®Studio for more information. It is possible
to choose a larger crystal package to save cost. The crystal should have an ESR of 60 Ωor
less.
CC2400 Evaluation Board
The Evaluation Board is used as a motherboard for the Evaluation Modules and provides
power and external connections.
Figure 7: CC2400EB Evaluation Board
Power supply section
The power supply section is configured by moving the jumpers located on the board. There
are three voltage regulators on the board, one for use by the FPGA, a 3.3 V regulator for
general use and a 1.8 V regulator for powering the CC2420. The voltage regulator for the
USB port
Serial port
Power
connections
Sockets for EM
Buttons
LEDs
SMA connectors
Test port
Reset button
Jumpers
DC jack

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FPGA is turned on under software control when the USB controller has been properly
configured.
A diode prevents permanent damage if wrong polarity is applied to the non-regulated input.
There are two power connectors; a 3.5mm DC jack-type connector allows you to connect an
unregulated battery eliminator easily (the positive supply is on the center pin), and two 5-pin
terminal blocks can be used to connect either an unregulated or regulated power supply.
An amperemeter can also be connected in order to measure the DC current drawn by the
CC2420. Since the CC2420 has two voltage supplies (Core and I/O), there are separate
current measurement loops for these two supplies. If you are not going to measure the
currents, short-circuit jumpers must be connected between the terminals, otherwise the
Evaluation Module will not be supplied with power.
A
4-7V
0V
ExtI
III
IOI
0V
ExtC
IIC
IOC
A
0V P2
P3
Figure 8: Power terminal block with amperemeters attached
Table 1: Power connector connections
Connector and pin Marking Description
P3 pin 1 4-7V Unregulated voltage in. Input to voltage regulators.
Equivalent with the DC jack input.
P3 pin 2 0V Circuit ground.
P3 pin 3 ExtI External I/O voltage. An externally applied voltage will
drive the I/O supply of the CC2420 (and the associated
FPGA pins) if the jumpers are set correctly.
P3 pin 4 III I/O supply current input. Insert an amperemeter
between this pin and the IOI pin to measure the current
drawn by the I/O supply of the CC2420.
P3 pin 5 IOI I/O supply current output. Insert an amperemeter
between this pin and the III pin to measure the current
drawn by the I/O supply of the CC2420.
P2 pin 1 0V Circuit ground.
P2 pin 2 0V Circuit ground.
P2 pin 3 Ext C External core voltage. An externally applied voltage
that will drive the core supply of the CC2420 if the
jumpers are set correctly.
P2 pin 4 IIC Core voltage current input. Insert an amperemeter
between this pin and the IOC pin to measure the
current drawn by the core supply of the CC2420.
P2 pin 5 IOC Core voltage current output. Insert an amperemeter
between this pin and the IIC pin to measure the current

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drawn by the core supply of the CC2420.
USB interface
The CC2400EB connects to a PC via a USB interface. SmartRF®Studio uses the USB
interface to control the CC2400EB. The USB interface can be used both to configure the
CC2420 and transfer data. Chipcon provides a Windows driver that is installed as part of the
SmartRF®Studio installation process. This driver must be present for SmartRF®Studio to
communicate with the CC2400EB.
Because USB is used, the CC2420DK will only function with PCs running Windows 98,
Windows ME, Windows 2000, Windows XP or newer. Windows NT and Windows 95 cannot
be used since they do not support USB.
RS-232 interface
A serial port is included on the CC2400EB. This is intended for debugging purposes, and
cannot be used to connect the Evaluation Board to SmartRF®Studio.
Jumpers
The jumpers are used to configure the Evaluation Board. The factory default settings are
shown below. This is the jumper setting when the CC2400EB voltage regulator is used to
power the CC2420.
Figure 9a CC2400EB voltage regulator selected on CC2420EM (Default jumper settings)
Figure 9b CC2420 internal voltage regulator selected on CC2420EM

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Jumpers
Name Default setting Description
VIO Between pins
6 and 8
Determines how the I/O supply of the CC2420 is supplied
with power. If the jumper is connected between pins 8 and
6, the 1.8V supply is used. If the jumper is connected
between pins 8 and 10, the 3.3V supply is used. If the
jumper is connected between pins 8 and 7, the I/O supply is
driven by the external voltage present on the ExtI pin on the
power connector.
VC Between pins
3 and 5
Determines how the core supply of the CC2420 is supplied
with power. If the jumper is connected between pins 3 and
5, power is supplied by the 1.8V regulator. If the jumper is
connected between pins 3 and 1, the core supply is driven
by the external voltage present on the ExtC pin on the
power connector.
C Between pins
4 and 6
Determines how power is supplied to the board. If the
jumper is connected between pins 4 and 6, the EB is
powered from the power connected to the power connector
or the power jack. If the jumper is connected between pins
6 and 8, the EB is powered from the USB bus. In this case,
the USB port the EB is connected to must be able to supply
500 mA current.
EEPROM
En.
Present Determines if USB configuration information is loaded from
EEPROM memory. If removed, the CC2400EB will report
itself as a default USB device. This jumper should always
be present during normal operation.
Microcontroller and FPGA
The CC2400EB has been built around a Cypress USB microcontroller and a Xilinx Spartan II
200E FPGA. This has been done to ensure maximum flexibility and is not representative for a
low-cost CC2420 application.
Both the microcontroller and the FPGA are RAM-based devices, and their configuration is
loaded via the USB interface on power-up. The CC2400EB must therefore be connected to a
PC to function properly.
Four LEDs and two buttons are included on the board for user interface purposes. The LEDs
are driven by the FPGA, while the buttons are connected to both the FPGA and the
microcontroller.
A reset button is provided, which will reset both the microcontroller and the USB interface.
The LEDs are used to indicate status when the CC2400EB is used together with SmartRF®
Studio.

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Connectors
The Evaluation Board is furnished with many connectors for easy access to various signals.
Test Port 1 (P17) and Test Port 2 (P5) are 2x10 pin pin-row connectors that are connected to
the FPGA and can be used to monitor various signals, including all the CC2420 signals. The
pin-out of these connectors is compatible with logic analyzer probes from Agilent.
The DTEST1 (P6) and DTEST2 (P7) SMA connectors are also connected to the FPGA and
can be used to output or input signals from/to the CC2420, respectively.
The ATEST1 (P9) and ATEST2 (P8) provide access to analog test signals from the CC2420.
The selection of what signals are available at the different connectors is done in SmartRF®
Studio.

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PCB layout, CC2400EB
The Evaluation Board is a 4-layer, 1.6 mm thick FR-4 PCB. Four layers are used because of
the routing requirements. Layers 1 and 4 are used for signal routing, layer 2 is a ground plane
and layer 3 is used for power routing. The majority of the components are mounted on the top
side of the PCB, while a few decoupling capacitors were put on the bottom side.
Figure 10: CC2400EB PCB layout, layer 1 (top left), layer 2 (top right), layer 3 (bottom left)
and layer 4 (bottom right)

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Figure 11: CC2400EB component placement, top side

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Figure 12: CC2400EB component placement, bottom side

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Schematics, CC2400EB

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