LA4905 查看數據表（PDF） - SANYO -> Panasonic

零件编号

产品描述 (功能)

比赛名单

LA4905

17-W, 2-Channel BTL AF High-Efficiency Power Amplifier for Car Stereo Systems

SANYO -> Panasonic 

LA4905

LA4905 High-Efficiency Technology

(1) Signal-following switching scheme

The LA4905 adopts a switching regulator scheme in

the power supply applied to the amplifier output stage.

The LA4905 power dissipation is reduced significantly

by having the output voltage of the switching regulator

follow the input signal. Furthermore, in combination

with the nonlinear amplifier scheme described below,

the LA4905 design reduces the number of switching

regulators to merely one circuit even though it is a

BTL 2-channel amplifier. (See Figure 1.)

(2) Nonlinear amplifier

The LA4905 adopts a nonlinear amplifier that has the

nonlinear characteristics shown in Figure 2 in the

amplifier signal system. This scheme does not use the

center point voltage of 1/2 VCC used in normal

amplifiers, but instead uses a voltage about 2 V lower.

This allows the design to dispense with the lower side

switching regulator.

This nonlinear amplifier has a structure based on a

differential amplifier that has symmetric negative

feedback circuits. Although the BTL output stage

positive and negative phase output waveform is a half-

wave waveform that is expanded and compressed as

shown in Figure 3, the combined output waveform at

the negative load terminal is identical to that output by

earlier products.

No. 5504-3/10

Share Link: