| 摘要 |
PURPOSE:To ensure circuit operation of an integrated circuit to a surge voltage by providing diodes connected in series in reverse direction between an input terminal and a high-potential side power source in a TTL integrated circuit device. CONSTITUTION:A negative surge voltage which was applied to an input terminal is absorbed by a low-potential side power source terminal 4 through a diode 3 formed in an integrated circuit 7. When a positive surge voltage is applied to the input terminal 1, it is absorbed by a high-potential side terminal 5 through a diode 8 and the diode 2 by breakdown of the diode 8. A breakdown voltage of the diode 8 is made lower than that of the diode 3. The breakdown voltage is adjusted by changing a concentration in a P-N junction. |
