CC2420ZRTC Datasheet, PDF (55/96 Pages) Texas Instruments – 2.4 GHz IEEE 802.15.4 / ZigBee-ready RF Transceiver

CC2420
33 Transmitter Test Modes
CC2420 can be set into different transmit
test modes for performance evaluation.
The test mode descriptions in the following
sections requires that the chip is first reset,
the crystal oscillator is enabled using the
SXOSCON command strobe and that the
crystal oscillator has stabilised.
33.1 Unmodulated carrier
An unmodulated carrier may be
transmitted
by
setting
MDMCTRL1.TX_MODE to 2 or 3, writing
0x1800 to the DACTST register and issue
a STXON command strobe. The transmitter
is then enabled while the transmitter I/Q
DACs are overridden to static values. An
unmodulated carrier will then be available
on the RF output pins.
A plot of the single carrier output spectrum
from CC2420 is shown in Figure 31 below.
Ref Lvl
3 dBm
3
0
-10
RBW
VBW
SWT
10 kHz
10 kHz
50 ms
RF Att
Unit
30 dB
dBm
A
-20
-30 _1AVG
-40
1SA
-50
-60
-70
-80
-90
-97
Center 2.45 GHz
Date:
23.OCT.2003 21:38:33
200 kHz/
Figure 31. Single carrier output
Span 2 MHz
SWRS041c
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