What Is Flyback Transformer?

Definition of flyback transformer and how it can generate high voltage with the help of a driver pulse.

A Flyback Transformer

The flyback transformer is an integrated transformer which mean it has built in rectifiers and divider networks and several low voltage windings. The purpose of a flyback transformer in a monitor or television is to generate high voltage about 24 kilovolts dc to picture tube or crt.

Older type of flyback transformer design have its high voltage diode built in outside and is called tripler. If any of the diodes spoilt you just have to replace the triple, But today, the flyback transformer came in one piece and all the high voltage diodes are molded inside the casing. If one of the diodes shorted inside you have to replace the whole unit.

The external features of a flyback transformer consist of a voltage divider where we called it as focus and screen. Inside the divider is actually a resistor networks control where the top control is always the focus adjustment and the bottom one is screen or G2. In order for a flyback transformer to function, a B+ supply voltage must enter to the primary winding and at the same time a horizontal output transistor or HOT must switch.

The HOT switching was done by horizontal driver circuit and with the help of a horizontal driver
transformer. If missing either one of the B+ voltage or signal to the HOT, the flyback transformer will not work. Of course there are many more factors that contribute to the malfunction of a flyback which i will explain in more details to you in this website.