
Si4322
Frequency Setting Command
bit
15
1
14
0
13
1
12
0
11
f11
10
f10
9
f9
8
f8
7
f7
6
f6
5
f5
4
f4
3
f3
2
f2
1
f1
0
f0
POR
AD57h
The 12-bit Frequency Setting Command < f11 : f0 >
has the value F. The value F should be in the range
The constant C is determined
by the selected band as:
of 96 and 3903. When F is out of range, the
previous value is kept. The synthesizer center
frequency f 0 can be calculated as:
f 0 = 8 * 10 MHz * (C + F/4000)
Receiver Setting Command
Band [MHz]
868
915
C
10
11
bit
15
1
14
1
13
0
12
0
11
0
10
0
9
0
8
0
7
d1
6
d0
5
g1
4
g0
3
r2
2
r1
1
r0
0
en
POR
C080h
Bit 7-6 < d1:d0 >:
Select the VDI (valid data indicator) signal:
Bit 5-4 < g1:g0 >:
d1
0
0
1
1
Set the LNA gain:
g1
0
0
1
1
d0
0
1
0
1
g0
0
1
0
1
VDI output
Digital RSSI Out (DRSSI)
Data Quality Detector Output (DQD)
Clock recovery lock
Always
G LNA (dB relative to max. G)
0
-6
-12
-18
Bit 3-1 < r2:r0 >:
Control the threshold of the RSSI detector:
r2
0
0
0
0
1
1
1
1
r1
0
0
1
1
0
0
1
1
r0
0
1
0
1
0
1
0
1
RSSIsetth [dBm]
-103
-97
-91
-85
-79
-73
-67
-61
The RSSI threshold depends on the LNA gain, the real RSSI threshold can be calculated:
RSSI th = RSSI setth + G LNA
Bit 0 < en >:
the low
Enables the whole receiver chain and crystal ocsillator when set. Enable/disable of the wake-up timer and
battery detector are not affected by this setting.
10