TDA7405_04 Datasheet, PDF (36/57 Pages) STMicroelectronics – EQUALIZER CARRADIO SIGNAL PROCESSOR

TDA7405
Figure 36. Blockdiagram of the Multipath-Detector
11.5 Quality Detector
The TDA7405 offers a quality detector output which gives a voltage representing the FM-reception conditions.
To calculate this voltage the MPX-noise and the multipath-detector output are summed according to the follow-
ing formula :
V_Qual = 1.6 (V_Noise-0.8 V)+ a (REF5V-V_Mpout).
The noise-signal is the PEAK-signal without additional influences (see noiseblanker description). The factor 'a'
can by programmed to 0.7 .... 1.15. The output is a low impedance output able to drive external circuitry as well
as simply fed to an AD-converter for RDS applications.
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