Patent ID: 6380797
Filing Date: 2002-04-30
Classification: H04L

Abstract:
An LVDS (Low Voltage Differential Signal) driver circuit having low sensitivity to fabrication process variation, power supply noise voltage variation, and operating temperature variation (PVT), comprising:a predriver having an input coupled to an internal circuit; a current source coupled to the predriver, the current source configured to produce a reference current through a first resistor included in the current source, the reference current configured to control an output swing of the predriver, the output swing determined by a ratio of the first resistor and a second, third, and fourth resistor in the predriver, wherein the second, third, and fourth resistor are equal, and wherein the ratio is the ratio of resistance between the first resistor and the second resistor such that a magnitude of the output swing is constant across PVT; and an output driver having an output for coupling an output signal to an external circuit, the output driver coupled to receive the output swing from the predriver and generate the output signal in accordance with the output swing such that a magnitude of the output signal is constant across PVT.