External Components Description

( See Figures1-4)

Components

Functional Description

1R

B

Prevents currents from entering the amplifier’s non-inverting input which may be passed through to the load

upon power down of the system due to the low input impedance of the circuitry when the undervoltage

circuitry is off. This phenomenon occurs when the supply voltages are below 1.5V.

2R

i

Inverting input resistance to provide AC gain in conjunction with R

3R

f

Feedback resistance to provide AC gain in conjunction with R

4C

i

(Note 13)

Feedback capacitor which ensures unity gain at DC. Also creates a highpass filter with R

πR

5C

S

Provides power supply filtering and bypassing. Refer to the Supply Bypassing application section for proper

placement and selection of bypass capacitors.

6R

V

(Note 13)

Acts as a volume control by setting the input voltage level.

7R

IN

(Note 13)

Sets the amplifier’s input terminals DC bias point when C

create a highpass filter at f

πR

8C

IN

(Note 13)

Input capacitor which blocks the input signal’s DC offsets from being passed onto the amplifier’s inputs.

9R

SN

(Note 13)

Works with C

10

C

SN

(Note 13)

Works with R

pole is set at f

πR

11

L (Note 13)

Provides high impedance at high frequencies so that R may decouple a highly capacitive load and reduce

the Q of the series resonant circuit. Also provides a low impedance at low frequencies to short out R and

pass audio signals to the load. Refer to Figure 4.

12

R (Note 13)

13

R

A

Provides DC voltage biasing for the transistor Q1 in single supply operation.

14

C

A

Provides bias filtering for single supply operation.

15

R

INP

(Note 13)

Limits the voltage difference between the amplifier’s inputs for single supply operation. Refer to the Clicks

and Pops application section for a more detailed explanation of the function of R

16

R

BI

Provides input bias current for single supply operation. Refer to the Clicks and Pops application section for

a more detailed explanation of the function of R

17

R

E

Establishes a fixed DC current for the transistor Q1 in single supply operation. This resistor stabilizes the

half-supply point along with C

Note 13: Optional components dependent upon specific design requirements.

Typical Performance Characteristics

Supply Current vs

Supply Voltage

PSRR vs Frequency

R

Ω, 80kHz BW

20059467

20059464

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