A 3-V CMOS low-distortion class AB line driver suitable for HDSLapplications

摘要

A fully differential CMOS line driver for use in high bit-ratendigital subscriber line (HDSL) services Is presented. The circuit isnfabricated in a single-poly quad metal 0.35-Μm process and achievesn<-70-dB total harmonic distortion while driving up to ±2.4-V,n200-kHz signals into 30 Ω with a 3-V supply. The circuit featuresna closed loop gain of 6.0 with minimal input capacitance (<200 fF).nThe circuit requires less than 20 mA of quiescent current and is capablenof delivering dynamic currents as large as 180 mA. The circuit is anmultistage amplifier utilizing nested-Miller compensation and annenhanced class AB output stage