Control circuit of associative memory and associative memory device

摘要

The present invention aims to reduce power consumption.;The timing control signal SR is brought to the low level to close the P-MOSFET 62 and open the N-MOSFET 60 and to set the NOT circuit 64 of the match line on the N-MOSFET 60 as a boundary. Side potential V_MATCHTo the power supply voltage V_DDUp. The comparison operation is performed in the associative memory cell 28 between them, and the P-MOSFET 42 is turned on or off according to the comparison result. Next, the control signal SR is set to the high level, the P-MOSFET 62 is turned off, and the N-MOSFET 60 is turned on. Thus, when the N-MOSFET 42 is turned on, the potential V_MATCHAnd potential V_MATCHBut the penetration current is blocked by the P-MOSFET 62 being turned off. When the N-MOSFET 42 is turned off, V_MATCHV_DD-V_tn(V_tnIs pulled up to the threshold voltage of the N-MOSFET 60), V_MATCHMOSFET 64 by the NOT circuit 64 and the P-MOSFET 66,_DDAnd the signal indicating the result of comparison is output from the NOT circuit 64. [;See FIG. 3.