CC2400 Chipcon AS, CC2400 Datasheet - Page 50

• Manufacturer Part Number: CC2400
• Description: 2.4 GHz RF Transceiver
• Manufacturer: Chipcon AS

adjacent
occupied bandwidth. In ‘true’ FSK systems
with
spectrum is inherently broad. By making
the frequency shift ‘softer’, the spectrum
can be made significantly narrower. Thus,
higher data rates can be transmitted in the
same bandwidth using GFSK.
Low cost systems
As the
channel performance without any external
filters, a very low cost system can be
made.
PCB Layout Recommendations
A four layer PCB is highly recommended.
The second layer of the PCB should be
the “ground-layer”.
The top layer should be used for signal
routing, and the open areas should be
filled with metallization connected to
ground using several vias.
The area under the chip is used for
grounding and must be connected closely
to the ground plane with several vias.
The ground pins should be connected to
ground as close as possible to the
package pin using individual vias. The de-
coupling capacitors should also be placed
as close as possible to the supply pins
and connected to the ground plane by
Chipcon AS
abrupt
CC2400
channel
SmartRF
frequency
provide 1 Mbps multi-
®
power
CC2400 PRELIMINARY Datasheet (rev. 1.1), 2003-10-02
shifting,
(ACP)
and
the
SmartRF
A differential antenna will eliminate the
need for a balun, and the DC biasing can
be achieved in the antenna topology, see
Figure 4.
Battery operated systems
In low power applications, the power down
mode should be used when not active.
Depending
requirement, the crystal oscillator core can
be powered during power down. See page
32 for information on how effective power
management can be implemented.
separate vias. Supply power filtering is
very important.
The external components should be as
small as possible (0402 is recommended)
and surface mount devices must be used.
Caution should be used when placing the
microcontroller
interference with the RF circuitry.
A Development Kit with a fully assembled
Evaluation Module is available. It is
strongly advised that this reference layout
is followed very closely in order to get the
best performance.
The schematic, BOM and layout Gerber
files for the reference designs are all
available from the Chipcon website.
on
in
®
the
order
CC2400
start-up
Page 50 of 73
to
avoid
time