LM4910MA National Semiconductor, LM4910MA Datasheet - Page 15

• Manufacturer Part Number: LM4910MA
• Description: Output Capacitor-less Stereo 35mW Headphone Amplifier
• Manufacturer: National Semiconductor

Application Information
The LM4910 is unity-gain stable and requires no external
components besides gain-setting resistors, input coupling
capacitors, and proper supply bypassing in the typical appli-
cation. However, if a very large closed-loop differential gain
is required, a feedback capacitor (C
shown in Figure 6 to bandwidth limit the amplifier. This
REFERENCE DESIGN BOARD and LAYOUT GUIDELINES
MSOP & SO BOARDS
(Note: R
PU
2 is not required. It is used for test measurement purposes only.)
f
) may be needed as
(Continued)
FIGURE 8.
15
feedback capacitor creates a low pass filter that eliminates
possible high frequency oscillations. Care should be taken
when calculating the -3dB frequency in that an incorrect
combination of R
off before 20kHz. A typical combination of feedback resistor
and capacitor that will not produce audio band high fre-
quency roll off is Rf = 20kΩ and C
nents result in a -3dB point of approximately 320kHz.
f
and C
f
will cause frequency response roll
f
= 25pF. These compo-
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