A class-D vertical booster for CRT

Integrated vertical boosters for the cathodic tube (CRT) are in charge of the vertical scanning of the electron beam on the CRT. They are amplifiers, and their function is to apply a sawtooth current on their load, which is a deflection yoke. The value of the current to be considered is typically around 2 A peak to peak. For such circuits in linear operating mode, the power dissipation is around 6 W in the integrated circuit for 2 W supplied to the load. The following circuit in class-D operating mode allows to reduce drastically the power dissipated in the integrated circuit and consequently the power consumption of the application. The power saving is typically 4 W compared with a traditional class-AB application. Taking in account the main power supply efficiency the total power saving is around 5 W