MULTI-VALUE QUANTIZING PHASE COMPARATOR WITH M-STAGE TWO-WAY COUNTER

摘要

PURPOSE:To operate a 2-way counter at low speed and to reduce the power consumption by adding an M-stage 2-way counter with a few capacity of free- run type to a multi-value quantizing phase comparator. CONSTITUTION:The M-stage 2-way counter 1-6 counts up with an L level input and counts down with an H level input. In the case of overflow, a phase lead information pulse is sent to the 2-way counter 1-2 and in the case of occurrence of underflow, a phase lag information pulse is sent to the counter 1-2. The counter 2 counts up with a phase lead information pulse and sends a 1 pulse elimination control signal D to a pulse addition/elimination circuit 1-8 when the result of count reaches 2N. Simultaneously, the counter 1-2 is reset to N. Moreover, the counter 1-2 counts down with the phase lag information pulse and when the result reaches 0, a 1 pulses addition control signal I is sent to the circuit 1-8 to reset the counter 1-2 to N. Thus, the counter 1-2 is operated at low speed.