External Components Description (Figure 1) (Continued)

Components

Functional Description

4.

C

S

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.

5.

C

B

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

6.

C

OUT

This output coupling capacitor blocks DC voltage while coupling the AC audio signal to the headphone

speaker. Combined with R

πR

Refer to the section, Proper Selection of External Components for an explanation of how to determine the

value of C

7.

R

PU

This is the pull up resistor to activate headphone operation when a headphone plug is plugged into the

headphone jack.

8.

R

S

This is the current limiting resistor for the headphone input pin.

9.

R

PD

This is the pull down resistor to de-activate headphone operation when no headphone is plugged into the

headphone jack.

Typical Performance Characteristics

THD+N vs Frequency

at V

Ω R

THD+N vs Frequency

at V

Ω R

20012737

20012738

THD+N vs Frequency

at V

Ω R

THD+N vs Frequency

at V

Ω R

20012739

20012740

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