Abstract:
An electrically programmable and erasable memory includes memory cells connected to word lines and to bit lines arranged in columns. Bit lines selection transistors are driven by bit lines selection signals. Column selection latches each includes a locking element for a column selection signal and a circuit for delivering a gate control signal which depends on the output of the locking element. Each column selection latch delivers, in addition to a gate control signal, a bit lines selection signal. This signal depends on the output of the locking element at least during programming and reading phases of the memory cells.
Abstract:
A column register of an integrated circuit memory, notably in EEPROM technology, is utilized in a method of writing a data word of 2P bits in the memory, where p is a non-zero whole number. The method includes the following steps: 1) erasing all the cells of the word; 2) loading 2q data in q high-voltage latches (HV1, HV3, HV5, HV7), and loading 2pnull2q other data in the 2pnull2q llow-voltage latches (LV0, LV2, LV4, LV6); and 3) programming 2q cells of the memory (M0, M2, M4, M6) as a function of the data memorized in the 2q high-voltage latches; as well as repeating 2pnullqnull1 times the following steps: 4) loading, in the 2q high-voltage latches, of 2q other data that were loaded in the 2q low-voltage latches at step 2); and 5) programming 2q other cells of the memory (M1, M3, M5, M7) as a function of the data memorized in the 2q high-voltage latches.
Abstract:
A circuit produces a voltage for the erasure or programming of a memory cell. The circuit includes a capacitor, and a discharge circuit connected to a first terminal of the capacitor. The discharge circuit includes a first transistor, a drain of which is connected to the first terminal of the capacitor. The first transistor activates the discharge circuit when a discharge signal is received by a gate of the first transistor. The discharge circuit includes a slow discharge arm and a fast discharge arm parallel-connected to the source of the first transistor. The discharge circuit produces a low discharge current or a high discharge current for discharging the capacitor as a function of an operating mode selection signal.