| 摘要 |
PROBLEM TO BE SOLVED: To provide a direction sensor indicating the change direction of a test signal. SOLUTION: A test switch 110, first and second accumulation devices 130 and 132, a comparison device 140, a normalization device 150 and a sampling(SMP) controller 120 are provided. The sample of the test signal is taken out during respective test cycles(TC). During the even-numbered TC, the SMP controller 120 transfers the even-numbered sample of the test signal to the first (second)) accumulation device 130 (132), and the signal is given to the first (second) input of the comparison device 140. The signal is compared with the even-numbered and odd-numbered samples. The comparison device 140 generates a first (second)) comparison signal showing the relative value of the sample and generates a comparison signal which alternately changes at every TC between '1' and '0' while the test signal moves in one direction. Thus, the normalization signal is generated by the SMP controller 120 and it is combined with the comparison signal by the normalization device 140. A direction signal outputted from the normalization signal has a prescribed digital value when the test signal changes in one direction. |
