Circuit for reading a semiconductor memory
AssigneeSTMicroelectronics S.r.l.
InventorsLorenzo Bedarida, Vincenzo Dima, Francesco Brani, Marco Defendi
Life of this patent
Estimating the term…
Abstract
A circuit for reading a semiconductor memory device includes at least one global circuit for generating a global reference signal for a respective plurality of cell-reading circuits disposed locally in the memory device. The circuit includes at least one circuit for replicating the reference signal locally in order to generate a local reference signal to be supplied to at least one respective cell-reading circuit.
Claims30
A circuit for reading cells of a semiconductor memory device comprising:
- a plurality of cell-reading circuits;
- a global circuit in the memory device for generating a global reference signal for the plurality of cell-reading circuits, the global circuit comprising a current mirror having a first branch comprising a reference-current generator and a second branch in which a second current proportional to a first current in the first branch flows;
- and
- at least one signal replicating circuit for replicating the global reference signal locally to generate a local reference signal to be supplied to at least one of the plurality of cell-reading circuits, the at least one local replicating circuit forming, with the second branch of the global circuit, a semi-local current mirror.
A semiconductor memory device comprising:
- a plurality of memory cells;
- and
- a circuit for reading the plurality of memory cells comprising
- a plurality of cell-reading circuits,
- a global circuit for generating a global reference signal for the plurality of cell-reading circuits, and comprising a current mirror having a first branch with a reference-current generator and a second branch in which a second current proportional to a first current in the first branch flows, and
- at least one signal replicating circuit for replicating the global reference signal to generate a local reference signal to be supplied to at least one of the plurality of cell-reading circuits, the at least one local replicating circuit forming, with the second branch of the global circuit, a semi-local current mirror.
A method for reading cells of a semiconductor memory device comprising a plurality of cell-reading circuits, and a global circuit for generating a global reference signal for the plurality of cell-reading circuits, the global circuit comprising a current mirror having a first branch with a reference-current generator and a second branch in which a second current proportional to a first current in the first branch flows, the method comprising:
- replicating the global reference signal with at least one signal replicating circuit to generate a local reference signal, the at least one local replicating circuit forming, with the second branch of the global circuit, a semi-local current mirror;
- and
- supplying at least one of the plurality of cell-reading circuits with the local reference signal to read the cells of the semiconductor memory device.
Dependencies are inferred from the claim text.