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Analog Front End IC TMS37122 - Reference Guide
August ’01
Figure 23: VWAKEB SENSITIVITY Diagram
2.10.3.3 Pulse Position Demodulator Threshold
Four bits are provided defining the Pulse Position Demodulation Threshold Count (cHdet) for decoding the
PPM Wake Pattern. The resulting Threshold Time (tHdet) depends on the used system frequency:
tHdet = cHdet / fTXThe numbers in below table are given for the nominal TIRIS System Frequency
(fTX=134.2 kHz),the default cHdet is 56:
0
50
100
150
200
250
300
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
CONFIGURATION
SEN
SIT
IVIT
Y
[
m
Vp
p
]
SPECmin
SPECnom
SPECmax