公开(公告)号：WO9714215A3

公开(公告)日：1997-05-15

申请号：PCT/IB9601040

申请日：1996-10-03

Applicant: PHILIPS ELECTRONICS NV ,  PHILIPS NORDEN AB

Inventor： BEHBAHANI FARBOD ,  FOTOWAT-AHMADY ALI ,  NAVID NASROLLAH S

IPC: H03K5/08 ,  H03F3/45 ,  H03K5/24 ,  H03L7/18 ,  H03K5/22

CPC classification number: H03K5/2445 ,  H03K5/2418

Abstract: A comparator has a simple high frequency signal path from input to output formed by two differentially connected transistors (Q1, Q2) with an output transistor (Q8, Q3) connected to each. A current control circuit maintains a constant total current flowing through the differentially connected transistors (Q1, Q2). The ratio of currents flowing through the differentially connected transistors (Q1, Q2) is initially set by a control circuit (I1, I2), so that the output of the comparator is predictable when powered up. The control circuit then gradually releases control, so that there is a smooth transfer to control by a reference signal input to the comparator.