A Low Ringing LVDS Driver With Common-mode Feedback Circuit

LVDS (Low-voltage Differential Signaling) is more and more used in systems which require keeping signal integrity and stable common-mode voltage.Because of imperfect termination and pad parasitic effects, there are ringing on the output voltage and common-mode voltage is unstable.This circuit designed applies a new pre-emphasis circuit technology which brings in a high frequency pole to decrease ringing and keep the output waves smooth.Besides, common-mode feedback circuit can stabilize common-mode voltage.In 0.18 μm process, the ringing is reduced 70 mV and the offset of common-mode voltage is less than 0.46%.