Texas Instruments CC2500 - Page 76

CC2500
S
WRS040
C
Page
76
of
89
0x1C: AGCCTRL1
–
AGC
C
ontrol
Bit
Field Name
Reset
R/W
Description
7
Reserved
R0
6
AGC_LNA_PRIORITY
1
R/W
Selects between two diffe
rent strategies for LNA and LNA
2
gain adjustm
ent. When 1, the LNA gain is dec
reased 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 relativ
e 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
(0000)
R/W
Sets the absolute RSSI threshold for
asserting carrier
sense. The 2
’s
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 (10
00)
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