| 摘要 |
PURPOSE:To improve the electrostatic strength by arranging a MOS transistor (TR) connected to an output terminal in parallel with an output buffer MOS TR. CONSTITUTION:A PMOS TR 3 and an NMOS TR 4 whose gates are connected to an input terminal 6 respectively, and used as the output buffer MOS TRs are provided to an output buffer circuit, the source of the PMOS TR 3 is brought into a power supply level VDD, while the source of the NMOS TR 4 is brought into a ground level. A dummy PMOS TR 1 acting like a protection diode is arranged in parallel with the PMOS TR 3 and a dummy MOS TR 2 acting like a protection diode is arranged in parallel with the NMOS TR 4. Thus, an excellent breakdown characteristic is obtained without sacrifycing the channel width W and the channel L. |
