| 摘要 |
PURPOSE:To provide the horizontal drive circuit at a variable scanning rate over a wide variable range used for a high definition display device. CONSTITUTION:A rectangular drive signal synchronous with a horizontal synchronizing signal is inputted to a constant current generating circuit section 28. A drive pulse subjected to current amplification is outputted to a horizontal output transistor(TR) 7 of a horizontal deflection circuit via a clamp circuit section 41. An excess charge extract circuit section 39 eliminates residual charges on a base of the TR 7 at a high speed. An input voltage of a power supply voltage control circuit section 51 is changed almost in proportion to a horizontal deflection frequency. Thus, a voltage outputted from a power supply VC3 is controlled by a TR 61, an optimum power supply is fed to the current generating circuit section 28, in which a tracing frequency range at a multi-scanning rate is considerably extended. |
