PA3332G-N24-R datasheet(6/9 Pages) UTC

6 / 9 page

PA3332

Preliminary

CMOS IC

UNISONICTECHNOLOGIESCO.,LTD

6 of 9

www.unisonic.com.tw

QW-R502-488.b



APPLICATION INFORMATION

Input MUX Operation

For the UTC PA3332, there exist two input signal paths (IN1 and IN2). Thus, for different input sources, the UTC

PA3332

has different gains with this prompt setting. When the IN1 / IN2 pin is in active high, this device operates in

IN2 input source; when it is in active low, this device operates in IN1 input source.

Bridged-Tied Load Mode Operation

The following figure A shows the BTL (Bridged-Tied Load) mode operation. The two linear amplifiers drive both

ends of the speaker load.

There are several advantages for using the BTL mode: first of all, the differential driving to the speaker load

means that when one side is slewing up, the other side is slewing down, and vice versa. The voltage swing on the

load is two times that on a ground reference load. In this mode, the peak-to-peak voltage VO(PP) on the load will be

double a ground reference configuration. 4 times output power on the load will be generated at the same power

supply rail and loading due to the voltage on the load is doubled. Further more, this BTL operation can cancel the dc

offsets which save the using of dc coupling capacitor that is needed to cancel dc offsets in the ground reference

configuration. Then the input network and speaker responses can only limit the low-frequency performance.

Moreover, the saving of dc coupling capacitors can minimize PCB space and the cost.

MUTE and SHUTDOWN Mode Operations

Circuits with mute and shutdown functions are contained in the UTC PA3332, which is designed to reduce IDD

(supply current) to the absolute minimum level during nonuse periods for battery-power conservation.

When pulling the shutdown pin (pin 8) high, all linear amplifiers will be deactivated to mute the amplifier outputs.

Then the device enters an extremely low current consumption condition, the supply current is less than 5µA. When

the mute pin (pin 14) is pulled high, it will force the activated linear amplifier to supply the VDD/2 dc voltage on the

output & shutdown the second linear amplifiers to mute the AC performance. The current dissipation will be smaller

in the mute mode operation than that in the BTL mode.

It is not allowed to leave the shutdown and mute pins floating, or unexpected conditions would occur for the

amplifier operations.

PA3332G-N24-R Datasheet(PDF) 6 Page - Unisonic Technologies