Patent ID: 6570415
Filing Date: 2003-05-27
Classification: H03K,H04L

Abstract:
A digital differential driver, comprising:a differential amplifier having a first and second power supply rail, comprises a first resistive element coupled to the first power supply rail, a first n-type MOS transistor having a gate, a drain and a source, the first resistive element coupled to the drain of the first n-type MOS transistor, a second resistive element coupled to the first power supply rail, a second n-type MOS transistor having a gate, a drain and a source, the second resistive element coupled to the drain of the second n-type MOS transistor, the source of the first n-type MOS transistor coupled to the source of the second n-type MOS transistor, and a current source coupled between the source of the second n-type MOS transistor and the second power supply rail; a first predriver having an input and an output, the output coupled to the gate of the first n-MOS transistor; and a second predriver having an input and an output, the output coupled to the gate of the second n-MOS transistor; wherein each of the first and second predriver comprises, an inverter coupled to the input, a p-type MOS transistor having a drain, a source and a gate, the source coupled to the first power supply rail, the gate coupled to the inverter; a third n-type MOS transistor having a drain, a source and a gate, the gate coupled to the gate of the p-type MOS transistor, the drain coupled to the drain of the p-type MOS transistor to form the output; and a fourth n-type MOS transistor having a drain, a source, and a gate, the drain coupled to the source of the third n-type MOS transistor, the source coupled to the second power supply rail, the gate coupled to the drain of the p-type MOS transistor.