| 摘要 |
PURPOSE:To make a phase shift adjustment precisely regardless of an oscillation frequency by providing an address signal generating circuit, a storage circuit, a D-A converter, a variable decoder, etc. CONSTITUTION:The output of a clock oscillator 9 is applied to the address signal generating circuit 10. This circuit 10 consists of a 360-scale counter, etc., and counts clock pulses corresponding to one scan from an address An to an address A359, resets itself, and restarts counting pulses, outputting its count output as an address signal. Storage contents read out of the storage addresses of an ROM11 successively by the address signal are converted into analog signals by a D-A converter 12, which outputs alternating signals. Part of the output of the circuit 10 is applied to the variable decoder 13. A rectangular wave shifted in phase from the output signal of the converter 12 by an angle set digitally by a phase shift angle setter 14 is obtained. Thus, the phase shift extent is set digitally regardless of the oscillation frequency of the oscillator 9. |
