IC Development of CMOS PWM Controller for Driving GaN-Based Switching Mode Power Converters

This paper proposed the result of the development and simulation of electrical circuit diagram, as well as the layout of PWM controller IC. The PWM controller IC was developed using HCMOS8D CMOS 0.18 μm 200 process. The PWM controller was designed to drive a GaN half-bridge IC with on-chip drivers and power HEMTs. The PWM controller consisted of eight functional blocks, is described in the paper. An on-chip oscillator with digital pulse counter and ramp generator unit provide frequency tuning range of 0.4 – 1 MHz. An error amplifier was integrated to PWM controller IC; the inverting output of error amplifier was internally connected to a 1.2 V voltage reference source. The PWM controller was simulated with the previously developed GaN half-bridge IC as part of a buck DC-DC converter. The obtained results demonstrated great potential of using a PWM controller as part of highly efficient electrical energy converters.