lm4897mm National Semiconductor Corporation, lm4897mm Datasheet - Page 5

• Manufacturer Part Number: lm4897mm
• Description: 1.1 Watt Audio Power Amplifier With Fade-in And Fade-out
• Manufacturer: National Semiconductor Corporation

External Components Description
Typical Performance Characteristics
Components
(Figure 1)
1.
2.
3.
4.
5.
C
C
R
C
R
S
B
i
i
f
Inverting input resistance which sets the closed-loop gain in conjunction with R
high pass filter with C
Input coupling capacitor which blocks the DC voltage at the amplifiers input terminals. Also creates a
highpass filter with R
an explanation of how to determine the value of C
Feedback resistance which sets the closed-loop gain in conjunction with R
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
THD+N vs Frequency
THD+N vs Frequency
V
V
DD
DD
PWR = 250mW
PWR = 100mW
= 2.6V, R
= 5V, R
L
L
= 8Ω
= 8Ω
i
i
at f
at f
C
C
= 1/(2πR
= 1/(2πR
200509A2
200509A4
i
i
C
C
i
i
).
). Refer to the section, Proper Selection of External Components, for
Functional Description
5
i
.
THD+N vs Frequency
THD+N vs Power Out
V
R
DD
PWR = 150mW
L
= 8Ω, f = 1kHz
= 3V, R
V
DD
i
.
= 5V
B
f
. This resistor also forms a
.
L
= 8Ω
200509A5
200509A3
www.national.com