Arrangement for generating a sawtooth current.

摘要

A line deflection stage comprises a line oscillator (LO), a driver (DR) and a line output transistor (TR1) the collector of which is connected through the parallel arrangement of a switching transistor (TR2) and a diode (D3) to a line deflection coil (Ly) and a scan capacitor (Cs). The deflection coil (Ly) and scan capacitor (Cs) are shunted by a diode (D2) whilst a flyback capacitor (Cf) is connected across the emitter-collector path of transistor (TR1). The line oscillator (LO) output is also applied to an input of a flyback time controller (TC) which produces a pulse output under the control of a control input (C). This pulse output is amplified by a further transistor (TR3) and an associated transformer (T) and applied to the base of transistor (TR2) to cut this transistor off for a controlled part of the flyback period to prevent the flyback capacitor immediately discharging and hence extend the flyback period.