Typical Performance Characteristics
IMD 60 Hz, 1:1
(Continued)
IMD 60 Hz, 7 kHz, 1:1
IMD 60 Hz, 7 kHz 1:1
DS011833-53
DS011833-54
DS011833-55
Mute Attenuation vs
Mute Current
Mute Attenuation vs
Mute Current
Large Signal Response
DS011833-58
DS011833-56
DS011833-57
Power Supply
Rejection Ratio
Common-Mode
Rejection Ratio
Open Loop
Frequency Response
DS011833-59
DS011833-60
DS011833-61
Application Information
GENERAL FEATURES
Mute Function:
The muting function of the LM3886 allows
the user to mute the music going into the amplifier by draw-
ing less than 0.5 mA out of pin 8 of the device. This is accom-
plished as shown in the Typical Application Circuit where the
resistor R
M
is chosen with reference to your negative supply
voltage and is used in conjuction with a switch. The switch
(when opened) cuts off the current flow from pin 8 to V
−
, thus
placing the LM3886 into mute mode. Refer to the Mute At-
tenuation vs Mute Current curves in the
Typical Perfor-
mance Characteristics
section for values of attenuation per
current out of pin 8. The resistance R
M
is calculated by the
following equation:
R
M
(|V
EE
| − 2.6V)/I8
where I8
≥
0.5 mA.
Under-Voltage Protection:
Upon system power-up the
under-voltage protection circuitry allows the power supplies
and their corresponding caps to come up close to their full
values before turning on the LM3886 such that no DC output
spikes occur. Upon turn-off, the output of the LM3886 is
brought to ground before the power supplies such that no
transients occur at power-down.
12
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