Components

Functional Description

1.

R

i

Inverting input resistance which sets the closed-loop gain in conjunction with R

forms a high pass filter with C

2.

C

i

Input coupling capacitor which blocks DC voltage at the amplifier’s input terminals. Also creates a

highpass filter with R

3.

R

f

Feedback resistance which sets closed-loop gain in conjunction with R

4.

C

S

Supply bypass capacitor which provides power supply filtering. Refer to the Application Information

section for proper placement and selection of supply bypass capacitor.

5.

C

B

Bypass pin capacitor which provides half supply filtering. Refer to Application Information section for

proper placement and selection of bypass capacitor.

Typical Performance Characteristics

THD+N vs Frequency

DS100094-9

THD+N vs Frequency

DS100094-10

THD+N vs Frequency

DS100094-11

THD+N vs Output Power

DS100094-12

THD+N vs Output Power

DS100094-13

THD+N vs Output Power

DS100094-14

Supply Current vs

Supply Voltage

DS100094-16

Power Derating Curve

DS100094-17

LM4870 Noise Floor

vs Frequency

DS100094-18

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