Université d’Aix Marseille, CNRS and STMicroelectronics Assigned Patent
Self-referenced and regulated sensing solution for phase change memory with ovonic threshold switch
By Francis Pelletier | February 22, 2024 at 2:00 pmUniversité d‘Aix Marseille, Marseille, France, Centre National De La Recherche Scientifique (CNRS), Paris, France, STMicroelectronics (Crolles 2) SAS, Crolles, France, and STMicroelectronics (Rousset) SAS, Rousset, France, has been assigned a patent (11875847) developed by Portal, Jean-Michel, Saint-Savournin, France, Della Marca, Vincenzo, Walder, Jean-Pierre, Marseille, France, Gasquez, Julien, Echirolles, France, and Boivin, Philippe, Venelles, France, for “self-referenced and regulated sensing solution for phase change memory with ovonic threshold switch.“
The abstract of the patent published by the U.S. Patent and Trademark Office states: “Memory devices such as phase change memory (PCM) devices utilizing Ovonic Threshold Switching (OTS) selectors may be used to fill the gap between dynamic random-access memory (DRAM) and mass storage and may be incorporated in high-end microcontrollers. Since the programming efficiency and reading phase efficiency of such devices is directly linked to the leakage current of the OTS selector as well as sneak-path management, a sense amplifier disclosed herein generates an auto-reference that takes into account the leakage currents of unselected cells and includes a regulation loop to compensate for voltage drop due to read current sensing. This auto-referenced sense amplifier, built utilizing the principle of charge-sharing, may be designed on a 28 nm fully depleted silicon-on-insulator (FDSOI) technology, provides robust performance for a wide range of sneak-path currents and consequently for a large range of memory array sizes, and is therefore suitable for use in embedded memory in high-end microcontroller.”
The patent application was filed on 2022-02-16 (17/673550).