| 摘要 |
Disclosed is a regulator circuitry (stabilizer) for controlling the output of an RF generator according to a programmable input signal. A power stage is responsive to the selected value of the programmable input signal to drive the RF generator at the desired power level. A forward power feedback control circuit monitors and controls the power output stage so that the desired RF output level is maintained at a constant level. In this particular mode of operation, RF output power is maintained constant and therefore independent of variations in gain due to temperature changes and other parameters which could effect the overall transfer function of said generator (and including mismatch of the generator into the load). When the stabilizer is selectively placed in a second operational mode, namely bias regulation, a different parameter, target bias voltage, is maintained at a constant level, independent of variations in the generator's transfer function such as gain changes due to temperature and so forth as mentioned above. A reflected power control feedback circuit limits the reflected power to a predetermined signal level and is arranged to reduce the signal applied to the power output stage to reduce the forward power whenever the reflected power exceeds the selected fixed level although the forward power will not be reduced below a level sufficient to support some reflected power. Forward power will never be reduced below the level required to support and maintain the reflected power level at the magnitude representing the reference voltage selected by the adjustment potentiometer connected to the reflected power sensors' non-inverting input.
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