| 摘要 |
PURPOSE:To ensure the diagnosis up to the final step of the digital circuit with diagnosis by extracting the feedback signal out of the driver circuit. CONSTITUTION:Each digital input signal 2, featuring H, is latched to each FF circuit 5 by timing signal 1, and the output signal 11 becomes H. Thus each transistor 8 is turned on, and each process signal 15 becomes L along with each load 9 functioning. At the same time, each diode 14 is turned on, and each signal 17 becomes L. And each feedback output signal 3 of driver circuit 16 becomes H via timing signal 4. Now in case transistor 8-1 has some fault and thus can not be turned on, process signal 15-1 becomes H along with diode 14-1 turned off and signal 17-1 changed to H each. And thus feedback output signal 3-1 becomes L to inform the circuit fault to the computer. Thus the diagnosis can be given up to the final step of the circuit. |
