TS4995 Datasheet, PDF (18/26 Pages) STMicroelectronics – 1.2 W fully differential audio power amplifier with selectable standby and 6 dB fixed gain

Application information
Figure 56. -3 dB lower cut-off frequency vs. input capacitance
All gain setting
Tamb=25°C
100
Minimum Input
Impedance
Typical Input
Impedance
10
Maximum Input
Impedance
0.1
0.5
1
Input Capacitor Cin (μF)
4.4
Power dissipation and efficiency
Assumptions:
● Load voltage and current are sinusoidal (V_out and I_out)
● Supply voltage is a pure DC source (V_CC)
The output voltage is:
V_out = V_peak sinωt (V)
and
I_out
=
V_{-----o---u---t -}
R_L
(A)
and
P_out
=
V_{-----p---e---a---k--}²_----
2R_L
(W)
Therefore, the average current delivered by the supply voltage is:
Equation 1
Icc _AVG =
2
-^V----^p---^e---^a---^k--
πR_L
(A)
The power delivered by the supply voltage is:
Equation 2
P_supply = V_CC I_ccAVG (W)
18/26
TS4995