Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
205 words
A semiconductor memory device comprising: a memory cell (14); a pair of bit lines (11, 11 ) connected to said memory cell; first precharging means (18), for precharging said pair of bit lines; a sense amplifier (22) for amplifying a potential difference between said pair of bit lines; a dummy bit line (41) having a load capacity equal to that of each of said pair of bit lines; a dummy memory cell (42) having a bit line drive capability equal to that of said memory cell; and second precharging means (43), for precharging said dummy bit line, characterized by further comprising: selecting means (12) for simultaneously selecting said memory cell and said dummy memory cell; dummy bit line potential sensing means (50) for sensing that the potential of said dummy bit line is changed from a precharge potential by a predetermined potential when said dummy memory cell is selected by said selecting means; and sense amplifier control means (51, 49, 52) for receiving an enable signal which enables an operation of said sense amplifier, and a sensed signal from said dummy bit line potential sensing means to determine an operation period of said sense amplifier, in response to both the enable and the sensed signals.
Claim 2
Dependent Claim
205 words
A semiconductor memory device comprising: a memory cell (14); a pair of bit lines (11, 11 ) connected to said memory cell; first precharging means (18), for precharging said pair of bit lines; a sense amplifier (22) for amplifying a potential difference between said pair of bit lines; a dummy bit line (41) having a load capacity equal to that of each of said pair of bit lines; a dummy memory cell (42) having a bit line drive capability equal to that of said memory cell; and second precharging means (43), for precharging said dummy bit line, characterized by further comprising: selecting means (12) for simultaneously selecting said memory cell and said dummy memory cell; dummy bit line potential sensing means (50) for sensing that the potential of said dummy bit line is changed from a precharge potential by a predetermined potential when said dummy memory cell is selected by said selecting means; and sense amplifier control means (51, 49, 52) for receiving an enable signal which enables an operation of said sense amplifier, and a sensed signal from said dummy bit line potential sensing means to determine an operation period of said sense amplifier, in response to both the enable and the sensed signals.
Claim 3
Dependent Claim
33 words
A device according to claim 1, characterized by further comprising latch means (45), controlled in response to an output from said sense amplifier control means, for latching an output from said sense amplifier.
Claim 4
Dependent Claim
49 words
A device according to claim 1, characterized in that said dummy bit line potential sensing means (50) comprises an inverter (50), connected to said dummy bit line, for inverting an output level of said sensing means when a potential of said dummy bit line exceeds a threshold voltage thereof.
Claim 5
Dependent Claim
77 words
A device according to claim 3, characterized in that said sense amplifier control means (22) comprises a first inverter (51), for inverting a level of an output signal from said inverter in said dummy bit line potential sensing means, a NAND gate for obtaining a negative AND logic of the output signal (49) from said inverter and the enable signal, and a second inverter (52), for inverting a level of the output signal from said NAND gate.
Claim 6
Dependent Claim
66 words
A device according to claim 2, characterized in that said latching means (45) comprises a control signal generator section (62) for receiving an output signal from said sense amplifier control means, to output first and second complimentary level control signals, and a latch section (61) for latching the output signal from said sense amplifier in response to the control signal from said control signal generator section.
Claim 7
Dependent Claim
58 words
A device according to claim 5, characterized in that said latch section comprises an inverter (63), controlled in response to the first control signal, for inverting a level of the output signal from said sense amplifier, and a flip-flop circuit (64, 65), controlled in response to the second control signal, for latching the output signal from said inverter.
Claim 8
Dependent Claim
85 words
A device according to claim 6, characterized in that said flip-flop circuit (64, 65) comprises a first inverter (64), for inverting a level of an output signal from said inverter in said latching means, to output the inverted signal as an output signal from said latching means, and a second inverter (65), controlled in response to the second control signal, for inverting a level of an output signal from said first inverter, to output the inverted signal to an input section of said first inverter.