| 摘要 |
PURPOSE:To obtain a malfunction preventing device with low cost by delivering an operating amount after the phase error information is replaced by the input of a comparison signal only in case a reference signal is supplied normally. CONSTITUTION:When a reference signal P2 is emitted by some reason, the count value of a counter 105 is not cleared. Thus the counter 105 continues a count-up operation. In addition, the output 113 of a flip-flop 115 is not set and kept under a reset state. When a comparison signal T2 is supplied, a latch 114 is inactive since the output 113 of the flip-flop 115 is kept at a low level. Thus the value of the counter 105 is not latched by a storage 106 despite the input of the comparison signal. Then the register 106 holds the value X1 latched previously as it is. |
