PURPOSE: To suppress the effect of a generated beat strip onto a screen by adopting the configuration such that a frequency division output of a frequency divider circuit has a frequency being a specific number of multiple of a frequency of a horizontal oscillation signal.

CONSTITUTION: The circuit consists of an oscillation circuit 1 generating a pulse signal S1 synchronously with a horizontal oscillation signal, a frequency divider circuit 2 frequency-dividing the pulse signal S1 by a predetermined frequency division ratio, a drive circuit 3 amplifying an output signal S2 of the frequency divider circuit 2, and a DC-DC converter configuration switching regulator 4 used to boost a DC voltage V1 applied externally. Then the frequency divider circuit 2 divides the pulse signal synchronously with the frequency of the horizontal oscillation signal to be a signal having a frequency of '(an integral number +0.5)×(horizontal oscillating frequency)' being a highest beat frequency and provides the frequency division output as a drive pulse signal of the switching regulator. Even when a beat stripe is generated on the screen, since the stripe is moved in the horizontal direction at a speed not sensed by human eyes, the effect on the screen is substantially eliminated.