LM4950TS datasheet(4/25 Pages) NSC

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Electrical Characteristics V

DD = 12V (Notes 1, 2) (Continued)

Note 6: Typicals are measured at 25˚C and represent the parametric norm.

Note 7: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).

Note 8: Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.

Note 9: Shutdown current is measured in a normal room environment. The Shutdown pin should be driven as close as possible to GND for minimum shutdown

current.

External Components Description Refer to (Figure 1.)

Components

Functional Description

1. R

This is the inverting input resistance that, along with R

F, sets the closed-loop gain. Input resistance RIN

and input capacitance C

IN form a high pass filter. The filter’s cutoff frequency is fc =1/(2

πR

INCIN).

2. C

This is the input coupling capacitor. It blocks DC voltage at the amplifier’s inverting input. C

IN and RIN

create a highpass filter. The filter’s cutoff frequency is f

C =1/(2

πR

INCIN). Refer to the SELECTING

EXTERNAL COMPONENTS, for an explanation of determining C

IN’s value.

3. R

This is the feedback resistance that, along with R

i, sets closed-loop gain.

4. C

The supply bypass capacitor. Refer to the POWER SUPPLY BYPASSING section for information about

properly placing, and selecting the value of, this capacitor.

5. C

BYPASS

This capacitor filters the half-supply voltage present on the BYPASS pin. Refer to the Application section,

SELECTING EXTERNAL COMPONENTS, for information about properly placing, and selecting the

value of, this capacitor.

20047072

FIGURE 2. Typical Stereo Single-Ended (SE) Audio Amplifier Application Circuit

LM4950TS Datasheet(PDF) 4 Page - National Semiconductor (TI)