Typical Performance Characteristics
Power Supply
Rejection Ratio
Common-Mode
Rejection Ratio
(Continued)
Open Loop
Frequency Response
DS100928-88
DS100928-89
DS100928-90
Supply Current vs
Case Temperature
Input Bias Current vs
Case Temperature
Mute Attenuation vs
Mute Current (per Amplifier)
DS100928-65
DS100928-67
DS100928-85
Mute Attenuation vs
Mute Current (per Amplifier)
DS100928-86
Application Information
MUTE MODE
The muting function of the LM4766 allows the user to mute
the music going into the amplifier by drawing more than
0.5 mA out of each mute pin on 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 conjunction with a switch. The switch
when opened cuts off the current flow from pin 6 or 11 to
−V
EE
, thus placing the LM4766 into mute mode. Refer to the
Mute Attenuation vs Mute Current curves in the
Typical Per-
formance Characteristics
section for values of attenuation
per current out of pins 6 or 11. The resistance R
M
is calcu-
lated by the following equation:
R
M
≤
(|−V
EE
| − 2.6V)/Ipin6
where Ipin6 = Ipin11
≥
0.5 mA.
Both pins 6 and 11 can be tied together so that only one re-
sistor and capacitor are required for the mute function. The
mute resistance must be chosen such that greater than 1 mA
is pulled through the resistor R
M
so that each amplifier is fully
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