LM4831VF National Semiconductor, LM4831VF Datasheet - Page 12

• Manufacturer Part Number: LM4831VF
• Description: IC AMP AUDIO PWR 1.5W AB 44LQFP
• Manufacturer: National Semiconductor
• Series: Boomer®r
• Type: Class ABr

Specifications of LM4831VF

• Output Type: 2-Channel (Stereo)
• Max Output Power X Channels @ Load: 1.5W x 2 @ 4 Ohm
• Voltage - Supply: 2.7 V ~ 5.5 V
• Features: Depop, Input Multiplexer, Microphone, Shutdown
• Mounting Type: Surface Mount
• Package / Case: 44-LQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: *LM4831VF

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Application Information
LM4831. The microphone input pin is connected to the in-
verting node of a CMOS op amp, so the input impedance is
very high (
BEEP CIRCUITRY
The beep circuitry is designed to allow a “sleeping” system to
temporarily power-up the LM4831 and output an audio alert
(“beep”). This feature might be used in a computer which is
“sleeping”, but needs to notify the user that the computer
batteries are low or that the user has new e-mail.
>
10M )
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The beep circuitry is activated by any edge which occurs on
the BEEP A-D pins. With a resistor, R
C
will be activated for R
R
The BEEP OUT pin is designed to signal other audio circuitry
that the LM4831 is powering up. Generally a CODEC will re-
ceive this signal and begin sending audio information to the
LM4831. Logically, the BEEP OUT signal is the result of an
XOR of the BEEP A-D pins.
beep
beep
, in parallel at the RC pin of the LM4831, the LM4831
and R
beep
are 1-10 M and 0.1µF.
beep
C
beep
seconds. Typical values for
beep
, and a capacitor,