Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
247 words
In a programmable read-only memory of the type having a matrix of intersecting column and row lines with a respective storage cell at and connecting the lines at the individual intersections, each storage cell having a circuit element connected to one of the lines and a current interruptable resistor connecting the circuit element to the other of the lines, column selection means for selecting column lines, and row switches connected to the row lines for selecting rows in response to address signals, each row switch comprising a differential amplifier having parallel connected control transistors controlled by the address signals and a reference transistor, and an emitter follower connecting the collectors of the control transistors to the respective row line, the improvement therein comprising: an input for connection to a switched voltage source to receive a first voltage during a reading operation and a second voltage during an information input operation; and switch means for each row switch including a current path connected between said input and the associated row line and a control input connected to the reference transistor of the differential amplifier, said switch means operated by said row switch upon selection of the associated row line and ineffective with respect to the row line when said input receives the first voltage and effective when said input receives the second voltage to support a current flow which is necessary for interrupting the storage cell resistors assigned to the associated row line and to selected column lines.
Claim 2
Dependent Claim
247 words
In a programmable read-only memory of the type having a matrix of intersecting column and row lines with a respective storage cell at and connecting the lines at the individual intersections, each storage cell having a circuit element connected to one of the lines and a current interruptable resistor connecting the circuit element to the other of the lines, column selection means for selecting column lines, and row switches connected to the row lines for selecting rows in response to address signals, each row switch comprising a differential amplifier having parallel connected control transistors controlled by the address signals and a reference transistor, and an emitter follower connecting the collectors of the control transistors to the respective row line, the improvement therein comprising: an input for connection to a switched voltage source to receive a first voltage during a reading operation and a second voltage during an information input operation; and switch means for each row switch including a current path connected between said input and the associated row line and a control input connected to the reference transistor of the differential amplifier, said switch means operated by said row switch upon selection of the associated row line and ineffective with respect to the row line when said input receives the first voltage and effective when said input receives the second voltage to support a current flow which is necessary for interrupting the storage cell resistors assigned to the associated row line and to selected column lines.
Claim 3
Dependent Claim
91 words
The improved memory of claim 1, wherein said switch means comprises: a switching transistor having a base, an emitter and a collector, said emitter connected to a reference potential; a first resistor connecting said base to said input; a second resistor connecting said collector to said input; and a plurality of emitter-follower stages connected in a series chain, each of said stages connected to said input, the first stage of the chain connected to said collector of said transistor and the last stage of the chain connected to a row line.
Claim 4
Dependent Claim
75 words
The improved memory of claim 2, wherein each of said emitter-follower stages comprises a transistor having a collector, an emitter and a base, said collector connected to said input, said base of the first stage connected to said collector of said switching transistor and each of the other bases connected to said emitter of the transistor of the previous stage, and a resistor connecting the base and emitter of adjacent stages to a predetermined potential.
Claim 5
Dependent Claim
29 words
The improved memory of claim 3, comprising: a diode connected to the junction of the base of said switching transistor and said first resistor and to a reference potential.
Claim 6
Dependent Claim
34 words
The improved memory of claim 4, wherein said diode is constituted by a transistor having an emitter connected to said junction and an collector and a base connected together and to the reference potential.
Claim 7
Dependent Claim
42 words
The improved memory of claim 4, wherein the circuit element of each storage cell comprises: a transistor having a base connected to appertaining row line, an emitter connected to the appertaining column line, and a collector connected to the switched voltage source.