Patent ID: 6236233
Filing Date: 2001-05-22
Classification: H03K

Abstract:
A circuit comprising:a first power supply providing a voltage above ground;a second power supply providing a voltage below ground;a translation circuit coupled between the first and second power supplies for determining if a first state in a first logic level of an input signal is high or low;a pull-down circuit coupled to the translation circuit for translating the input signal to a low state in the second logic level if the first state is low;a pull-up circuit coupled to the translation circuit for translating the input signal to a high state in a second logic level if the first state is high;wherein the translation circuit comprises:a first circuit through which a current flows when the first state is low, comprising:a first transistor receiving an inverted input signal;a second transistor coupled in series to the first transistor;a first resistor coupled in series between the second transistor and the first power supply; anda second resistor coupled in series between the first transistor and the second power supply; anda second circuit through which a current flow when the first state is high, comprising:a third transistor receiving the input signal;a fourth transistor coupled in series to the third transistor;a third resistor coupled between the fourth transistor and the first power supply; andthe second resistor coupled in series between the third transistor and the second power supply.