LM4878IBP National Semiconductor, LM4878IBP Datasheet - Page 11

• Manufacturer Part Number: LM4878IBP
• Description: IC AMP AUDIO PWR 1W MONO 8USMD
• Manufacturer: National Semiconductor
• Series: Boomer®r
• Type: Class ABr

Specifications of LM4878IBP

• Output Type: 1-Channel (Mono)
• Max Output Power X Channels @ Load: 1W x 1 @ 8 Ohm
• Voltage - Supply: 2 V ~ 5.5 V
• Features: Shutdown, Thermal Protection
• Mounting Type: Surface Mount
• Package / Case: 8-MicroSMD
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: *LM4878IBP; *LM4878IBP/NOPB; LM4878IBPCT

Application Information
The LM4878 is unity-gain stable and requires no external
components besides gain-setting resistors, an input coupling
capacitor, and proper supply bypassing in the typical appli-
cation. However, if a closed-loop differential gain of greater
than 10 is required, a feedback capacitor may be needed as
shown in Figure 2 to bandwidth limit the amplifier. This
feedback capacitor creates a low pass filter that eliminates
possible high frequency oscillations. Care should be taken
(Continued)
FIGURE 2. Higher Gain Audio Amplifier
11
when calculating the -3dB frequency. An incorrect combina-
tion of R
20kHz. A typical combination of feedback resistor and ca-
pacitor that will not produce audio band high frequency rolloff
is R
-3dB point of approximately 320 kHz. It is not recommended
that the feedback resistor and capacitor be used to imple-
ment a band limiting filter below 100kHZ.
3
= 20kΩ and C
3
and C
4
4
can cause a frequency roll off below
= 25pf. These components result in a
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