TC32306FTG
2015-10-01
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- High Frequency Detector Auto Off
After DET_out Signal is H level in Signal Detection function, High Frequency Detector will be
automatically turned off by the setting of register: h’1A[D1] = “1”. That may reduce the influence on
RF receiver sensitivity. When both Delay Detection and High Frequency Detector are enabled
(h’10[D0]Sel_Det = ”0” and h’0F[D4]Hdet_en = ”1”), this function is valid. To use this function again
after Auto Off, set status to Battery Saving / Standby or digital block being disabled. This setting will
be valid immediately after the data input to register:h’1A.
(3)
LPF for FSK
The cutoff frequency of LPF for FSK is about 20 kHz.
(4)
Signal Detections
In FSK, TC32306FTG is available 3 types of Signal Detections, RSSI Detection / Noise Detection /
Preamble Detection. These Signal Detections have various sensitivity and accuracy, so select Signal
Detection suitable to the application. Signal Detection parameters, such as Enable/Disable, detection
interval, threshold level of detection and number times for judgment are set by register. These Signal
Detections show signal situations as “Signal Detection” or “No Signal Detection” and these outputs
depend on number of continuous times to be set in advance, which is above or below the threshold
level.
Notice:
“Signal Detection” and “No Signal Detection” depend on TC32306FTG internal judgment. Those don’t
guarantee actual signal situations. It may be possible to be neither “Signal Detection” nor “No Signal
Detection”.
Table 6-22 Signal Detections in FSK
Item
RSSI Detection
Noise Detection
Preamble Detection
Method
Monitoring integrated signal level
at IF AMP.
Monitoring noise level near 34
kHz in FSK demodulation
signal.
Monitoring preamble signal at Data COMP.
output (Data pattern:10101...), .
Signal Detection
Enable / Disable
h'0F[D7]Drssi_en
0:Disable / 1:Enable
h'0F[D5]Ndet_en
0:Disable / 1:Enable
h'0F[D6]Preamble_en
0:Disable / 1:Enable
Detection Interval
h'1A[D7:D6]Ntime1..0
0.338 - 2.7ms (4steps)
Cannot set RSSI detection and Noise detection independently.
h'1A[D2]Pre_DetTrig
0: signal period
1: signal bit
Detection Threshold
Level
h'16[D7:D0]DRSSI_Th7..0
8bit(256steps)
h'19[D7:D2]Ndet_Th5..0
6bit(64steps)
Preamble detection Interval (512steps)
h'18[D7]Pre_Time8/h'17[D7:D0]Pre_Time7..0
Preamble detection error margin(128steps)
h'18[D6:D0]Err_Margin6..0
Detection
Number of Times for
judgment
One time detection
One time detection
h'1A[D4:D3]Pre_DetCount1..0
Signal Detection
No Signal Detection
3-6 period /
6-12bit(4steps)
3 period / 4 bit
Signal Detection
above threshold.
(RSSI_DET_out signal = “H”)
below threshold.
(NDET_out signal = “H”)
Continuously within the error margin.
(Preamble_DET_out signal = “H”)
No Signal Detection
Below threshold level.
Above threshold level.
Continuously without the error margin.
- Each results of Signal Detection (RSSI_DET_out signal / NDET_out signal / Preamble_DET_out signal) can be monitored
in User Test. Each results of “No Signal Detection” cannot be monitored directly.
- About each setting in detail, see “Register Overview & Description”.
TC32306FTG outputs DET_out signal (Judgment of “Signal Detection”) and Un_DET_out signal
(Judgment of “No Signal Detection”) to DET_TMONI1 pin and DET_TMONI2 pin, as the result of 3
overall signal detection judgment.
