A high-efficiency 4/spl times/20 W monolithic audio amplifier for automobile radios using a complementary DMOS BCD technology

In modern auto radios the output power can be as high as four times 20 W. This feature can be obtained with a single monolithic integrated circuit. Such an output power gives rise to a power dissipation, for music, of about 27 W in a standard class-AB amplifier. Since in the auto radio package, space available for the heat sink is limited, efficiency improvement is desirable. To achieve this, the authors present a monolithic quad audio power amplifier, which reduces the power dissipation of the standard class-AB configuration 45% with a music signal. A rail-to-rail output stage and a lossless power switch are implemented in a dedicated complementary DMOS bipolar-CMOS-DMOS (BCD) technology.