| 摘要 |
1,056,578. Switching circuits. COMPAGNIE GENERALE D'ELECTRICITE. May 14, 1964 [May 14, 1963; Nov. 29, 1963], No. 20214/64. Heading H3T. [Also in Division H1] A PNPNP device (see Division H1) is used to switch current flow between points A and B in response to pulses applied to input coil 23. According as the potential of A is higher or lower than that of B, one of the transistors 25 is normally blocked and so effectively an open circuit and the other conducting and effectively a short circuit (Fig. 8, not shown, depicts such normal condition). A suitable pulse applied to coil 23 will raise the potential of terminal C of the PNPNP device and also, because of the connection of the transistor bases to point 41 on coil 24, unblock the blocked transistor. This enhances the effect of the pulse applied to terminal C and ensures unblocking of the PNPNP device to make the A-B circuit connection. This connection can be switched out by a negative pulse to input coil 23. The transistors may be replaced by diodes connected between points A-D and B-D. |
