Panasonic tc-22lh1 technical guide Service Manual

 
A CCF tube needs high voltage. The starting voltage is generally over 1,000 volts and 
the operating voltage is generally between 200 and 500 volts rms. 
Most CCFT DC to AC inverters are tuned switchers designed to produce a specific 
voltage, frequency and output current when a designated tube is connected to the 
output. The classic current-fed two-transistor inverter has a tuned resonating output, 
tuned resonating input and inductive dc input which provides for good power transfer 

 

and high operating efficiency. 

he type of circuit depicted in Figure 6 inherently produces a pure sine-wave output, but 

r tube 

Figure 6 

T
the voltage and current waveforms are both distorted when they are applied to a CCF 
tube, which is a highly nonlinear device. The transition from the starting voltage to the 
operating voltage in this circuit is implemented by a small internal series output 
capacitor, which serves as the ballast, providing impedance, and allowing prope
current after the tube has been ignited. 

 

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