HEATER VOLTAGE GENERATION

摘要

A heater circuit (H) according to the invention comprises a stabilizing power supply (SPS) with a control input (CT) which receives a control signal (Cs) to control the value at which the heater voltage (Vh) has to be stabilized. A timing circuit (TC) generates the control signal (Cs) such that the heater voltage (Vh) has a nominal value (Vhn) in a normal operation phase, and such that the heater voltage (Vh) has a boost value (Vhb) higher than the nominal value (Vhn) during a boost period (Tb) of a start-up phase (Ts). The normal operation phase is defined as the phase during which the heater (HE) is sufficiently hot to enable display of a picture with good quality. The start-up phase (Ts) is the phase during which the display apparatus starts up and the heater (HE) warms up.