| 摘要 |
PURPOSE:To implement a high speed in circuit operation by using inverter circuits utilizing bipolar transistors as an input protecting circuit for a MOS type transistor at an input stage. CONSTITUTION:An input signal from an input pad 10 is inverted by an inverter circuit 11, again inverted by an inverter 12 and sent into a MOS transistor Tr (a) at an input stage. At this time, when the inverter circuits 11 and 12 are implemented at a level of micro miniaturization (e.g., a minimum pattern dimension is about 1.5mum) in the MOS Tr, the signal delay time per inverter stage is about 0.5 nsec. The time is shortened by 1 nsec in comparison with 2 nsec in a conventional example. Bipolar Trs basically have a large capacity based on a P-N junction and paths for large current. Therefore they have a structure, which is highly reistive against electrostatic breakdown, and sufficiently display input protecting action against a gate input. The internal circuit pattern and the input protecting circuit pattern are reduced. The speed of the input circuit operation is made higher. The signal delay time in the input protecting circuit is shortened. Thus a the higher speed of an MOS integrated circuit is implemented. |
