TDA7245 Datasheet, PDF (4/11 Pages) STMicroelectronics – 5W AUDIO AMPLIFIER WITH MUTING AND STAND-BY

TDA7245
ELECTRICAL CHARACTERISTCS (Continued)
STAND-BY FUNCTION
Symbol
Vst-by
I_{st- by}
ATT_st-by
V_t
I_{d st-by}
Parameter
Pin 5 DC Voltage
Pin 5 Current
Stand-by Attenuation
Stand-by Threshold (pin 5)
Stand-by Current
Test Condition
Mute SW Open (play)
Mute SW Closed (st-by)
f = 100Hz to 10kHz
V_S = 14V
Min. Typ. Max. Unit
6.4
V
160 280
µA
70
90
dB
3.8
V
1
3
mA
Note (*):
MUSIC POWER CONCEPT
MUSIC POWER is ( according to the IEC clauses n.268-3 of Jan 83) the maximal power which the amplifier is capable of producing across the
rated load resistance (regardless of non linearity) 1 sec after the application of a sinusoidal input signal of frequency 1KHz.
According to this definition our method of measurement comprises the following steps:
1) Set the voltage supply at the maximum operating value -20%
2) Apply a input signal in the form of a 1KHz tone burst of 1 sec duration; the repetition period of the signal pulses is > 60 sec
3) The output voltage is measured 1 sec from the start of the pulse
4) Increase the input voltage until the output signal show a THD = 10%
5) The music power is then V^2out/R1, where Vout is the output voltage measured in the condition of point 4) and R1 is the rated load impedance
The target of this method is to avoid excessive dissipation in the amplifier.
Figure 2: Schematic Diagram
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