CC2500_06 Datasheet, PDF (70/84 Pages) Texas Instruments – Single Chip Low Cost Low Power RF Transceiver

CC2500
0x1C: AGCCTRL1 – AGC control
Bit Field Name
Reset R/W Description
7 Reserved
R0
6 AGC_LNA_PRIORITY
1
R/W Selects between two different strategies for LNA and LNA 2
gain adjustment. When 1, the LNA gain is decreased first.
When 0, the LNA 2 gain is decreased to minimum before
decreasing LNA gain.
5:4 CARRIER_SENSE_REL_THR[1:0] 0 (00) R/W Sets the relative change threshold for asserting carrier
sense
Setting
Carrier sense relative threshold
0 (00)
Relative carrier sense threshold disabled
1 (01)
6 dB increase in RSSI value
2 (10)
10 dB increase in RSSI value
3 (11)
14 dB increase in RSSI value
3:0 CARRIER_SENSE_ABS_THR[3:0] 0
R/W Sets the absolute RSSI threshold for asserting carrier
(0000)
sense. The 2-complement signed threshold is programmed
in steps of 1 dB and is relative to the MAGN_TARGET
setting.
Setting
Carrier sense absolute threshold
(Equal to channel filter amplitude when AGC
has not decreased gain)
-8 (1000) Absolute carrier sense threshold disabled
-7 (1001) 7 dB below MAGN_TARGET setting
…
…
-1 (1111) 1 dB below MAGN_TARGET setting
0 (0000) At MAGN_TARGET setting
1 (0001) 1 dB above MAGN_TARGET setting
…
…
7 (0111) 7 dB above MAGN_TARGET setting
PRELIMINARY Data Sheet (Rev.1.2) SWRS040A
Page 70 of 83