TDA7406 Datasheet, PDF (43/64 Pages) STMicroelectronics – Car radio signal processor

TDA7406
11 Quality detector
Quality detector
The TDA7406 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 following 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 from 0.7 to 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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