LM4766TF National Semiconductor, LM4766TF Datasheet - Page 9

• Manufacturer Part Number: LM4766TF
• Description: IC,Audio Amplifier,DUAL,BIPOLAR,ZIP,15PIN,PLASTIC
• Manufacturer: National Semiconductor

Specifications of LM4766TF

• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

10
11
12
13
14
15
16
17
18
19
20
External Components Description
Note 14: Optional components dependent upon specific design requirements.
1
2
3
4
5
6
7
8
9
Components
R
R
R
C
(Note 14)
C
R
(Note 14)
R
(Note 14)
C
(Note 14)
R
(Note 14)
C
(Note 14)
L (Note 14)
R (Note 14)
R
C
R
(Note 14)
R
R
R
C
S
1
B
i
f
i
S
V
IN
IN
SN
SN
A
A
INP
BI
E
M
M
Prevents currents from entering the amplifier’s non-inverting input which may be passed through to the load
upon power down of the system due to the low input impedance of the circuitry when the undervoltage
circuitry is off. This phenomenon occurs when the supply voltages are below 1.5V.
Inverting input resistance to provide AC gain in conjunction with R
Feedback resistance to provide AC gain in conjunction with R
Feedback capacitor which ensures unity gain at DC. Also creates a highpass filter with R
Provides power supply filtering and bypassing. Refer to the Supply Bypassing application section for proper
placement and selection of bypass capacitors.
Acts as a volume control by setting the input voltage level.
Sets the amplifier’s input terminals DC bias point when C
create a highpass filter at f
Input capacitor which blocks the input signal’s DC offsets from being passed onto the amplifier’s inputs.
Works with C
Works with R
The pole is set at f
Provides high impedance at high frequencies so that R may decouple a highly capacitive load and reduce
the Q of the series resonant circuit. Also provides a low impedance at low frequencies to short out R and
pass audio signals to the load. Refer to Figure 4.
Provides DC voltage biasing for the transistor Q1 in single supply operation.
Provides bias filtering for single supply operation.
Limits the voltage difference between the amplifier’s inputs for single supply operation. Refer to the Clicks
and Pops application section for a more detailed explanation of the function of R
Provides input bias current for single supply operation. Refer to the Clicks and Pops application section for
a more detailed explanation of the function of R
Establishes a fixed DC current for the transistor Q1 in single supply operation. This resistor stabilizes the
half-supply point along with C
Mute resistance set up to allow 0.5mA to be drawn from pin 6 or 11 to turn the muting function off.
→ R
Current curves in the Typical Performance Characteristics section.
Mute capacitance set up to create a large time constant for turn-on and turn-off muting.
Mute switch that mutes the music going into the amplifier when opened.
M
is calculated using: R
SN
SN
to stabilize the output stage by creating a pole that reduces high frequency instabilities.
to stabilize the output stage by creating a pole that reduces high frequency instabilities.
C
= 1/(2πR
C
M
= 1/(2πR
SN
A
≤ (|V
.
C
SN
EE
). Refer to Figure 4.
IN
| − 2.6V)/l where l ≥ 0.5mA. Refer to the Mute Attenuation vs Mute
C
IN
Functional Description
). Refer to Figure 4.
9
BI
.
IN
is present in the circuit. Also works with C
i
.
f
.
INP
.
i
at f
C
www.national.com
= 1/(2πR
IN
i
to
C
i
).