Abstract:
A memory system comprising a semiconductor memory for storing digital data, said memory being connectable to a control device in order to receive an address signal and to make data selected through the output-available address signal. The system is characterised in that it comprises a generating circuit for activating a wait signal to be forwarded to the control device during reading operations in such a way as to indicate the non-availability of the data to be read. The generating circuit is such to deactivate the wait signal, in such a way as to indicate the availability of the data to be read, following a waiting time interval correlated with an effective access time for said memory.
Abstract:
A device and method for programming an electrically programmable memory applies at least one first programming pulse to a group of memory cells (MC1-MCk) of the memory, accesses the memory cells of the group to ascertain a programming state thereof, and applies at least one second programming pulse to those memory cells in the group whose programming state is not ascertained to correspond to a desired programming state. A voltage applied to a control electrode of the memory cells is varied between the at least one first programming pulse and the at least one second programming pulse according to a forecasted change in biasing conditions of the memory cells in the group between said at least one first and at least one second programming pulses. Undesired over-programming of the memory cells is thus avoided.
Abstract:
The device includes a circuit for sector remapping having a CAM (Content Addressable Memory) unit, associated to and in data communication with a multiplexer unit. The CAM unit detects that a sector is defective, it provides the pre-programmed address of a replacing sector and it activates the multiplexer which performs the replacement. The defective sectors and the corresponding locations of the address map are therefore advantageously positioned to the rear to the addressing area. The addressing area is consequently continuous, thus allowing the information to be easily stored and retrieved.
Abstract:
A circuit (115,145,150), for programming a non-volatile memory device (100) having a plurality of memory cells (105), includes a plurality of driving elements (115) each one for applying a program pulse to a selected memory cell to be programmed. The driving elements are suitable to be supplied by a power supply unit (120,125), and a control means (145,150) controls the driving elements (115). The control means (145,150) includes means (150,205) for determining a residual capacity of the power supply unit, and a selecting means (145) selectively enables the driving elements (115) according to the residual capacity. A method of programming, an integrated circuit, and a computer system are also disclosed.