PA3431G-N20-R datasheet(6/11 Pages) UTC

6 / 11 page

PA3431

CMOS IC

UNISONIC TECHNOLOGIES CO., LTD

6 of 11

www.unisonic.com.tw

QW-R502-225.C



APPLI CAT I ON I N FORM AT I ON

Shutdown Mode Operating

SHUTDOWN PIN INPUT

THE AMPLIFIER’S OUTPUT

LOW

MUTE(the current of this device will be reduced to 110µA )

HIGH

BTL

OTHERS

Don’t Care

CI(Input Capacitor)

The value of CI is important to consider as it directly affects the bass performance of the application circuit.

When CI is required to allow the amplifier to bias the input signal to the proper dc level for optimum operation, it’s

value can be calculate by this equation:

CI=1/(2

πRIFC)

RI:Input Impedance

FC:High-pass Filter’s Frequency

The low leakage tantalum or ceramic capacitors are suggested to be used as the input coupling capacitors,

because of the small leakage current of the input ca-pacitors will cause the dc offset voltage at the input to the

amplifier that reduces the operation headroom, especially at the high gain applications. It is important to let the

positive side connecting to the higher dc level of the application when using the polarized capacitors.

Gain setting (VS GAIN0, GAIN1 and RI)

Gain setting is determined by GAIN0 and GAIN1. The gains listed in the next table are realized by changing the

taps on the input resistors inside the amplifier which will cause the internal input impedance(R I) to be dependent on

the gain setting as we can see listed in the next table.

AV(dB)

GAIN0

GAIN1

RI(k

Ω)

15.6

21.6

PA3431G-N20-R Datasheet(PDF) 6 Page - Unisonic Technologies