| 摘要 |
PURPOSE:To obtain a circuit having high input protective characteristics against electrostatic breakdown, latch-up, etc. by inserting a pinch resistor having predetermined IV characteristics in series with an input terminal for the input protective circuit. CONSTITUTION:When an input protective circuit for an IC is constituted by an N<+>P<-> type diode 5, a pull-up transistor 6 and other transistors, a pinch resistor 5 having IV characteristics shown in the graph is connected at a midpoint between the diode 5 and the transistor 6 connected in series, and the pinch resistor is connected to an input terminal 7. The center and both ends of the resistor 4 are connected to a source or a drain for the transistor 6 through diodes. Accordingly, even when the voltage of input signals swings to -V2 from V1, outflow currents from the IC can be limited by the pinch resistor 4, a gate input level 8 is not brought to a negative value by outflow currents from the transistor 6, and the high speed of response is displayed. |
