| 摘要 |
PURPOSE:To realize a system which improves a fault detection rate and facilitates a test by selecting one of output signals from plural halfway circuit pars and an output stage circuit part according to an input signal to an input terminal. CONSTITUTION:An input line from the input terminal 2 to an input stage circuit part 3 is branched and connected to a decoder circuit 9. Then, output lines from the respective halfway circuit parts 4-6 to the output stage circuit part 7 are branched and connected to a switch circuit 10 and an output line from an output circuit part 8 is also connected at the same time; and the circuit 10 switches and sends out input signals from those input lines to an output terminal. The switching of the input signals by the circuit 10 is controlled with the output signal of the circuit 9. When the output signal of the circuit 10 indicates input signals to the circuit parts 4-6 at the time of the fault detection test of the circuit parts 4-6 or the input signal from the circuit 8 at the time of the fault detection test of the whole circuit 1, fault detection is easily tested without installing any new test terminal. |
