CC2520_11 Datasheet, PDF (20/133 Pages) Texas Instruments – 2.4 GHZ IEEE 802.15.4/ZIGBEE RF TRANSCEIVER

CC2520 DATASHEET
2.4 GHZ IEEE 802.15.4/ZIGBEE® RF TRANSCEIVER
SWRS068 – DECEMBER 2007
5.11 Optional Temperature Compensation of TX
Using the on-chip temperature sensor (or any other sensor), it is possible to adapt the settings to the actual
temperature. This will reduce the variation in output power over temperature, which in the range -40ºC to
125ºC can be significant.
For this purpose, a TX setting only suited for high-temperature operation has been found (F7125deg). This
setting should only be used above 70 degrees, but will significantly reduce the drop in output power at high
temperatures.
Table 2: F7125deg setting, only suited for high temperature operation (only changes from
recommended settings shown)
Register
TXCTRL
FSCTRL
Setting (hex)
94
7B
Comment
Increased output power at high temperatures.
Increased output power at high temperatures.
Table 3: Suggested TXPOWER register settings for different temperatures
Temperature -40 -30 -20 -10 10 30 50
70
90
110
125
ºC
Recommended 13 13 AB AB F2 F7 F7 F7125deg F7125deg F7125deg F7125deg -
Setting
Typical Output 3.6 3.3 4.3 4.1 4.2 4.3 3.5
3.6
2.7
1.9
1.1
dBm
Power
TYPICAL OUTPUT POWER WITH AND WITHOUT
TEMPERATURE COMPENSATION
8.0
4.0
With compensation
0.0
Without compensation
(+5dBm setting)
-4.0
-40
10
60
110
TEMPERATURE (ºC)
MINIMUM OUTPUT POWER WITH AND WITHOUT
TEMPERATURE COMPENSATION
8.0
4.0
0.0
With
compensation
-4.0
Without compensation
-8.0
(+5dBm setting)
-12.0
-40
10
60
110
TEMPERATURE (ºC)
20
WWW.TI.COM