An improved source follower with wide swing and low output impedance

This paper presents a wide-swing source follower with resistive load capability designed in TSMC 0.18 mum CMOS technology. Two additional amplifiers are employed to enlarge its input swing. The resultant stability problem is solved by a simple compensation scheme based on analysis of the system transfer function. Under a 1.8V supply the source follower, when loaded by a 1KOmega resistor and shifting the level of 500 mV, achieves total harmonic distortion (THD) of -95.6 dB with 0.2Vpp input and -67.6 dB with 1.2Vpp input at 10 MHz respectively.