| 摘要 |
<p>PURPOSE:To correct accurately the phase without being affected by a characteristics of a reference signal by using a digital output signal of each A/D converter to the same corresponding sampling part of each cycle of a reference signal so as to calibrate the phase. CONSTITUTION:When a phase calibration mode is selected, a switch 40 selects a reference signal generator 58 by the control of a CPU 66 and a switch 52 selects an amplifier 42. Multiplexers 60, 62 select respectively A/D converters 12, 14 by the CPU 66 and a multiplexer 82 selects an address counter 80. Memories 20, 22 are brought into the write mode by the control of a trigger/memory control circuit 78, the A/D converters 12, 14 sample an analog signal to convert the signal into a digital signal. Then is the read mode, the multiplexers 60, 62 select a bus 64 and the multiplexer 82 select a CPU address. The CPU 66 reads a stored digital value and selects a digital value near a ground potential.</p> |
