FUSING CIRCUIT OF PHASE TRIMMING UNIT

摘要

PURPOSE: A phase trimming circuit is provided to prevent an error operating of phase trimming by checking error of bit setting on anti-fusing status. CONSTITUTION: A switch(SW1) outputs the fusing voltage(Vpower) controlled by fusing enable-signal(Fen) approving fusing voltage(Vpower) at one side. A fusing status voltage output part(10) creates voltage fixed(V2) according to fusing on or off of A fusing resister(Rfuse) on enabling the switch. A standard voltage output part(20) outputs standard voltage for comparison with voltage outputted from the fusing status voltage output part. A comparator determines whether decision fusing-on or not by comparing with the two voltage. The one side of fusing status voltage output part(10) is connected with a source of each NMOS transistor and a current mirror composed of a pair of NMOS transistor, and the other side is composed of grounded fusing resister(Rfuse) and A resister(R3). The fusing status voltage is outputted to reverse-input-terminal of the comparator(COMP1) by the resister(R3).