A CONVERGENCE CORRECTION VOLTAGE WAVEFORM (15) IS APPLIED TO A POWER AMPLIFIER CIRCUIT (100). AN OUTPUT STAGE OF THE POWER AMPLIFIER DRIVES A DEFLECTION COIL (L1) OF A CATHODE RAY TUBE WITH A CONVERGENCE CORRECTION CURRENT (ICORR), WHICH IS PROPORTIONAL TO THE CONVERGENCE CORRECTION VOLTAGE WAVEFORM. A DIFFERENTIAL VOLTAGE POTENTIAL (VDIFF, Q24 OR VDIFF, Q26) ACROSS AN OUTPUT DEVICE (Q8, Q24 OR Q10, Q26) OF THE OUTPUT STAGE IS COMPARED AGAINST A PREDETERMINED REFERENCE VOLTAGE (VREF). AS THE DIFFERENTIAL VOLTAGE POTENTIAL BEGINS TO DROP BELOW THE PREDETERMINED REFERENCE VOLTAGE, A BUCK-TOPOLOGY VOLTAGE REGULATOR (60 OR 61), WHICH IS COUPLED TO THE OUTPUT DEVICE, TURNS ON. THE DIFFERENTIAL VOLTAGE POTENTIAL IS THEREBY MAINTAINED AT A LEVEL GREATER THAN THE PREDETERMINED REFERENCE VOLTAGE.FIGURE 1
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