US 5,206,544 A · CMOS off-chip driver with reduced signal swing and reduced power supply disturbance

Abstract

An off-chip driver circuit which includes a complementary pair of field effect transistor source followers connected in a non-inverting series circuit arrangement. The driver circuit includes an n-channel device to pull the output up to the positive supply less the threshold drop across the device and a p-channel device to pull the output down for the opposite transition to within a threshold voltage drop above ground of the p-channel device. The driver circuit includes means for eliminating body effect by connecting the n(p)-well of the p(n) channel transistor to the output node. The driver circuit provides a reduced swing low noise output which reduces the collapse of the power supply. The driver circuit provides an appropriate impedance match to the output transmission line, so that the output transmission line can be terminated to eliminate reflections.

Claims18

Dependent claims

A driver circuit comprising:

a pair of complementary field effect transistors each having source, drain and gate terminals, the sources of each of said pair of transistors being connected in series at an output node, the drain of a first of said pair of transistors being connected to a first voltage potential and the drain of a second of said pair of transistors being connected to a second voltage potential which is at a lower voltage than said first voltage potential, the gates of each of said pair of transistor being coupled to an input node, a well of one of said pair of transistors being connected to said output node.

Dependencies are inferred from the claim text.

CMOS off-chip driver with reduced signal swing and reduced power supply disturbance

Life of this patent

CMOS off-chip driver with reduced signal swing and reduced power supply disturbance

Life of this patent

Abstract

Claims18