TDA7491HV Datasheet, PDF (19/26 Pages) STMicroelectronics – 20 W + 20 W dual BTL class-D audio amplifier

TDA7491HV
Application information
7.2
Gain setting
The gain of the TDA7491HV is set by the two inputs, GAIN0 (pin 30) and GAIN1 (pin 31).
Internally, the gain is set by changing the feedback resistors of the amplifier.
Table 7.
Gain settings
GAIN0
0
0
1
1
GAIN1
0
1
0
1
Nominal gain, G_v (dB)
20
26
30
32
7.3
Input resistance and capacitance
The input impedance is set by an internal resistor Ri = 60 kΩ (typical). An input capacitor
(Ci) is required to couple the AC input signal.
The equivalent circuit and frequency response of the input components are shown in
Figure 25. For Ci = 220 nF the high-pass filter cut-off frequency is below 20 Hz:
fc = 1 / (2 * π * Ri * Ci)
Figure 25. Device input circuit and frequency response
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