General Purpose Interface Receiver Using Short Channel CMOS Devices
Original Publication Date: 1986-Jan-01
Included in the Prior Art Database: 2005-Mar-08
It is very difficult to design a high-performance off-chip receiver using FET (field-effect transistor) devices that will accept small voltage levels and power supply. This is due partially to the inherently lower Gm (transconductance) of such devices as compared to bipolar devices. This article describes how such a design can now be achieved using available "very short channel" FETs. Fig. 1 shows the schematic of a standard CMOS (complementary metal oxide semiconductor) differential amplifier with a single-ended output. Devices Q1 and Q2 are the input devices with a static discharge structure attached. The devices Q11, Q12, and Q13 generate approximately 1.05 volts, which is used for the signal reference and current source gate bias.