Integrated 60-V class-D power output stage with 95% efficiency in a 0.13μm SOI BCD process

In this paper we present a highly-efficient 60V class-D power stage design in a 0.13μm SOI-based BCD process. The integrated output stage consists of a full H-bridge, level shifter, ramp generator, comparator, integrator, and preamplifier. Its performance was found to be better than previously published output stages implemented in SOI based BCD processes, which are typically more complex and costly. The achieved results demonstrate that second-order class-D amplifiers can achieve total-harmonic-distortion (THD) performance compatible with the specifications of high end audio applications (THD & 0.029%). The output stage has a maximum efficiency of 95% and delivers up to 600mW into a 8Ω Bridge-Tied Load (BTL) with a total area of 1.5 mm².