PAM8012

Document number: DSxxxxx Rev. 1 - 3

7 of 14

www.diodes.com

October 2012

© Diodes Incorporated

PAM8012

A Product Line of

Diodes Incorporated

Application Information

Test Setup for Performance Testing

Notes:

1. The AP AUX-0025 low pass filter is necessary for class-D amplifier measurement with AP analyzer.

2. Two 33μH inductors are used in series with load resistor to emulate the small speaker for efficiency measurement.

Anti-Saturation

The Anti-saturation feature provides continuous automatic gain adjustment to the amplifier through an internal circuit. This feature enhances the

perceived audio loudness and at the same time prevents speaker damage from occurring.

The Anti-saturation works by detecting the output. The gain changes depending on the supply voltage, and the attack and release time. The

gain changes constantly as the audio signal increases and/or decreases. The gain step size for the Anti-saturation is 0.4 dB. If the audio signal

has near-constant amplitude, the gain does not change. Table 1 shows the Anti-saturation variable description.

Table 1. PAM8012 Anti-Saturation Variable Description

Varible

Description

Value

Gain

The pre-set gain of the device when the Anit-saturation is inactive.

The fixed gain is also the initial gain when the device comes out of

shutdown mode or when the Anti-saturation is disabled.

18dB

(Maximum)

Attack Time

The minimum time between two gain decrements.

128µS

Release Time

The minimum time between two gain increments.

256mS

PL Terminal Function

The voltage value of PL sets the PAM8012 maximum output by an external resistor. Refer to table 2 for anti-saturation and power limit selection.

Table 2. PAM8012 Anti-Saturation and Power Limit Variable Description

0

Open

EN

VDD

PL: OFF

Anti-Sat: OFF

PL: ON

Anti-Sat: ON

PL: OFF

Anti-Sat: ON

VDD/2

PL: OFF

Anti-Sat: OFF

PL: ON

Anti-Sat: OFF

PL: ON

Anti-Sat: OFF