LM4871
External Components Description
Components
1.
2.
R
i
C
i
(Figure
1)
Functional Description
Inverting input resistance which sets the closed-loop gain in conjunction with R
f
. This resistor also forms a
high pass filter with C
i
at f
C
= 1/(2π R
i
C
i
).
Input coupling capacitor which blocks the DC voltage at the amplifiers input terminals. Also creates a
highpass filter with R
i
at f
c
= 1/(2π R
i
C
i
). Refer to the section,
Proper Selection of External Components,
for an explanation of how to determine the value of C
i
.
Feedback resistance which sets the closed-loop gain in conjunction with R
i
.
Supply bypass capacitor which provides power supply filtering. Refer to the
Power Supply Bypassing
section for information concerning proper placement and selection of the supply bypass capacitor.
Bypass pin capacitor which provides half-supply filtering. Refer to the section,
Proper Selection of External
Components,
for information concerning proper placement and selection of C
B
.
3.
4.
5.
R
f
C
S
C
B
Typical Performance Characteristics
THD+N vs Frequency
THD+N vs Frequency
THD+N vs Frequency
DS100008-3
DS100008-4
DS100008-5
THD+N vs Output Power
THD+N vs Output Power
THD+N vs Output Power
DS100008-6
DS100008-7
DS100008-8
Output Power vs
Supply Voltage
Output Power vs
Supply Voltage
Output Power vs
Supply Voltage
DS100008-9
DS100008-10
DS100008-11
3
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