Patent ID: 6720798
Filing Date: 2004-04-13
Classification: H03K,H03M,H04L

Abstract:
A differential line driver comprising:first, second, third and fourth cascode transistors driven by a first voltage, wherein drains of the first and third transistors are connected to a first output of the differential line driver, and wherein drains of the second and fourth transistors are connected to a second output of the differential line driver; first, second, third and fourth switching transistors connected in series with corresponding first, second, third and fourth cascode transistors and driven by a corresponding data signal; and first and second compound transistors inputting a class AB operation signal to control output currents of the compound transistors, wherein the first compound transistor is connected to sources of the first and second switching transistors, wherein the second compound transistor is connected to sources of the third and fourth switching transistors, and wherein the first compound transistor includes first, second and third field effect transistors (FET's) connected in series with each other and with sources of the first and second switching transistors, and a fourth FET connected across the second FET, a gate of the fourth FET driven by the class AB operation signal.