| 摘要 |
1,250,433. Selection circuits. MESSERSCHMITT-BOLKOW-BLOHM G.m.b.H. 28 Jan., 1970 [7 Feb., 1969], No. 4124/70. Heading G4H. A circuit for selecting one of a number of relays or other loads, e.g. for test purposes, comprises a switching matrix having n vertical control lines and m horizontal lines there being a relay or other load R at each intersection connected between a row line m and a thyristor T which when fired by a signal on the corresponding vertical line, connects the relay to a Zener diode Z. Each Zener diode is shunted by a switch S which, at the same time as the signal is applied to the line n is closed to select the row of relays L containing the one to be selected. The control lines n are connected to the thyristors T through diodes D preventing interference between lines. When the selected thyristor has fired, the switch S is opened to prevent any of the other relays in that row being operated by chance signals. |
