Power source circuit

Abstract

Abstract PURPOSE:To obtain a circuit suitable to the regulator of horizontal deflecting frequency variable type display equipment by synchronizing the switching frequency of the regulator to a horizontal deflecting frequency or the integer-fold or 1/integer frequency. CONSTITUTION:A deflecting output level detecting circuit 21 outputs a direct current voltage Eref in accordance with the size of the output level of a horizontal deflecting circuit 3. When the voltage Eref is inputted to a comparator 11 and the polarity of the circuit in a switching regulator 6 is specified so that +Eb' can be lowered when the Eref rises, the Eref is coincident with a reference voltage Es. When the Eref is constant, the output level of the circuit 3 comes to be constant regardless of the frequency and finally, a deflecting current Iy of a constant amplitude irrelative to the deflecting frequency flows at a deflecting coil 4. On the other hand, a saw-tooth-wave generating circuit 20 generates a saw-tooth-waves S of the same frequency synchronized with this from the pulse coincident with the horizontal deflecting frequency. A pulse width modulating circuit 13 outputs the size discriminating result of an input Eo and the saw-tooth-wave S with a binary level, turns on and off a transistor 14 and changes a square wave Ro in accordance with the deflecting frequency.

Inventors

• 👤 Shigeru Kashiwagi
• 👤 柏木　茂

Bibliographic Details