PAM8019

Document number: DS38822 Rev. 1 - 2

9 of 12

www.diodes.com

May 2016

© Diodes Incorporated

PAM8019

Application Information

Non Clip Power Limit (NCPL) Function

When output reaches the maximum power setting value, the NCLP circuits will decrease the gain to prevent the output waveform from clipping

helping to prevent speaker damage and maximizing audio performance. The PL pin is used to set and control the NCPL function.

Table 1: NCPL Setting Threshold vs. Output

AGC Function

Output Power

PL pin floating

NCPL function disabled

Mute Operation

The MUTE pin is an input for controlling the Class-D output state of the PAM8019. A logic low on this pin enables the outputs and logic high on this

pin disables the outputs. This pin may be used to quickly disable or enable the outputs without a volume fade. Quiescent current is listed in the

electrical characteristic table. The MUTE pin can be left floating due to the internal pull-down.

Shutdown Operation

In order to reduce power consumption while not in use, the PAM8019 contains shutdown circuit to turn off the amplifier

’s bias circuit. The amplifier

is turned off when logic low is placed on the

SD pin. The SD pin can be left floating due to the internal pull-up.

Under voltage Protection

External under voltage detection can be used to shut down the PAM8019 before an input device can generate a pop. The shutdown threshold at

the UVP pin is 1.2V. The user selects a resistor divider to obtain the shutdown threshold and hysteresis for the specific application.

The threshold can be determined as below:

With the condition: R3 >> R1//R2

V

Hysteresis = 5µA x R3 x (R1+R2)/ R2

Power Supply Decoupling

The PAM8019 is a high performance CMOS audio-amplifier that requires adequate power supply decoupling to ensure the THD and PSRR are as

low as possible. Power supply decoupling also prevents oscillation caused by long leads between the amplifier and the speaker. The optimum

decoupling is achieved by using two capacitors of different types that target different types of noise on the power supply leads. A good Low-

the higher frequency transients, spikes or digital hash on the line. Filtering lower-frequency noise signals a large capacitor of 10µF or greater should

be placed near the audio amplifier.