公开(公告)号：JPH0818444A

公开(公告)日：1996-01-19

申请号：JP15309995

申请日：1995-06-20

Applicant: SYMBIOS LOGIC INC

Inventor： MAIKERU BII ANDAASON ,  KENESU SHII SHIYUMITSUTO

IPC: H03K3/0231 ,  H03K3/03 ,  H03K3/354 ,  H03L7/099 ,  H03L7/10

Abstract: PURPOSE: To considerably change the frequency range of a delay cell and to realize multiplex range VCO by changing the delay cell of a ring oscillator, to add a current supply source to a booster inverter and to selectively increase/ decrease current. CONSTITUTION: The delay cell is basically a current control converter. The transmission delay of the respective cells changes by changing current to the delay cell and the frequency of ICO changes. The booster inverter constituted of four FET transistors 40, 42, 44 and 46 is incorporated in a main current stub inverter and therefore stronger delay cell is realized. When the strength of the booster inverter increases, the frequency range of VCO shifts to the higher frequency. When the strength of a booster decreases, the frequency range of VCO shits to the lower frequency. Thus, the frequency range is considerably changed by increasing/decreasing the current of booster inverter current supply sources 50, 52, 54 and 56. Then, a multiplex range operation can be realized.