Abstract A cascade sense amplifier includes section separated sense amplifiers, a cascade wiring and a main sense amplifier. The main sense amplifier has a capacitance regulation element provided at a base potential of input transistors constituting a data input end. The element is comprised of a metal oxide semiconductor (MOS) transistor for forming a capacitance corresponding to a potential V SS mainly forming a capacitance by the cascade wiring. A size of the element is determined in the manner that the base potential drop time of the transistors is equal to a potential drop time of the cascade wiring when a power source voltage V CC drops. Even though the power source voltage V CC drops, the transistors have no cut-off condition so as to prevent the read-out time from delaying. Especially, if the element is comprised of a MOS transistor, it is possible to use an extremely thin gate insulation layer as a dielectric, thereby suppressing an increase of a chip size.
A cascade sense amplifier, comprising a plurality of section separated sense amplifiers, each of which opposes to each of section cell array, and which senses data stored in corresponding section cell array; a cascade wiring portion for commonly connecting a plurality of output ends of said plurality of section separated sense amplifier; a main sense amplifier having a bipolar transistor as a data input end and for amplifying each output from each of said section separated sense amplifiers through said cascade wiring portion; and a capacitance regulation element for regulating a capacitance of a base potential of said bipolar transistor constituting the data input end of said main sense amplifier.
Claim 2
Dependent Claim
110 words
A cascade sense amplifier, comprising a plurality of section separated sense amplifiers, each of which opposes to each of section cell array, and which senses data stored in corresponding section cell array; a cascade wiring portion for commonly connecting a plurality of output ends of said plurality of section separated sense amplifier; a main sense amplifier having a bipolar transistor as a data input end and for amplifying each output from each of said section separated sense amplifiers through said cascade wiring portion; and a capacitance regulation element for regulating a capacitance of a base potential of said bipolar transistor constituting the data input end of said main sense amplifier.
Claim 3
Dependent Claim
31 words
The cascade sense amplifier according to claim 1 wherein said capacitance regulation element is comprised of an element for setting a capacitance equal to a capacitance of said cascade wiring portion.
Claim 4
Dependent Claim
22 words
The cascade sense amplifier according to claim 2 wherein said capacitance regulation element is comprised of an metal oxide semiconductor (MOS) transistor.
Claim 5
Dependent Claim
62 words
The cascade sense amplifier according to claim 2 wherein a capacitance value of said capacitance regulation element is set in a manner such that a potential drop time of a base of said bipolar transistor in said main sense amplifier is equal to a potential drop time of said cascade wiring portion when a power supply voltage of said sense amplifier fluctuates.
Claim 6
Dependent Claim
20 words
The cascade sense amplifier according to claim 1 wherein said capacitance regulation element is comprised of an N-channel MOS transistor.
Claim 7
Dependent Claim
61 words
The cascade sense amplifier according to claim 5 wherein a capacitance value of said capacitance regulation element is set in the manner that a potential drop time of a base of said bipolar transistor in said main sense amplifier is equal to a potential drop time of said cascade wiring portion when a power supply voltage of said sense amplifier fluctuates.
Claim 8
Dependent Claim
61 words
The cascade sense amplifier according to claim 1 wherein a capacitance value of said capacitance regulation element is set in the manner that a potential drop time of a base of said bipolar transistor in said main sense amplifier is equal to a potential drop time of said cascade wiring portion when a power supply voltage of said sense amplifier fluctuates.