TDA7415CB Datasheet, PDF (19/50 Pages) STMicroelectronics – Car radio multimedia signal processor

TDA7415CB
Description of the audio processor
The CD-Changer- and Auxiliary/Navigation-inputs are quasi-differential inputs, where the
'out-of-phase' or ground signals of both channels share one common input. The Minidisk-
input (MD) may be reconfigured for a true mono differential input as required by many phone
units. Please note that all differential inputs dampen the signal by 3dB.
Additionally, each differential input-pin features a 'fast charge'-switch (*) allowing quickly
charging external, large coupling capacitors upon power-on of the device. For normal
operation, these switches need to be released by programming the corresponding bit.
For programming of the Input-section, see the programming chapter
5.2
5.2.1
Main signal processing path
The main-signal-processing path incorporates a classical three-band tone control (bass, mid
and treble) that is preceded by a gain-adjust amplifier and completed by a dedicated room
acoustics notch-filter (Room-EQ, see figure 1) that allows defeating the main car-body
resonance.
Hereafter, the filters composing the tone control and room-EQ will be presented.
Bass filter
There are four parameters programmable in the bass-filter stage.
1. Control Range: Figure 4 shows the control range in the frequency domain at 60Hz
center frequency.
Figure 4. Bass control range; f_C= 60Hz, Q= 1.0
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