公开(公告)号：CA1250351A

公开(公告)日：1989-02-21

申请号：CA457030

申请日：1984-06-20

Applicant: IBM

Inventor： GAUDENZI GENE J ,  NORSWORTHY JOHN P ,  PHAN NGHIA V ,  REEDY DENNIS C

IPC: H03K5/02 ,  H03K17/04 ,  H03K17/60 ,  H03K17/615 ,  H03K19/088 ,  H03K19/092

Abstract: LOW POWER OFF-CHIP DRIVER CIRCUIT Power dissipation in an off-chip driver circuit is decreased by utilizing a selectively switched transistor to discharge the base of the output pull-down transistor, and by using a large resistance in the base current path for the first stage of the Darlington pull-up transistors. An additional transistor having a larger emitter area and coupled to a lower potential source is connected in parallel with the normal phase-splitter transistor to provide additional output current sinking capability, and a current mirror is connected to control the current through both the phase splitting transistor and the additional transistor to control the turn-on transition of the pull-down output transistor.