{
  "patent_number": "US 3387286",
  "country": "US",
  "title": "How Robert Dennard Invented the One-Transistor DRAM Memory Cell",
  "original_title": "Field-effect transistor memory",
  "summary": "IBM's 1967 patent for a memory cell using a single transistor and a capacitor, which became the foundation for all modern computer RAM.",
  "what_it_does": "This patent describes a memory cell that stores a single bit of data using only one field-effect transistor and one capacitor. Before this, computer memory required multiple transistors per bit, which made it bulky, expensive, and power-hungry. By shrinking the design to a single transistor, this invention allowed engineers to pack millions of bits of data into a tiny silicon chip. When the transistor is activated, it allows a charge to be stored in the capacitor, representing a one or zero.",
  "what_it_does_not_cover": [
    "Does not cover static RAM (SRAM) which uses multiple transistors to hold data without needing periodic refreshing.",
    "Does not cover the manufacturing processes for etching these transistors onto silicon wafers.",
    "Does not cover magnetic core memory or other non-semiconductor storage technologies."
  ],
  "filed": "1967-07-14",
  "granted": "1968-06-04",
  "expires": "1987-07-14",
  "status": "expired",
  "holder": "International Business Machines Corp",
  "holder_url": "https://patentbrief.org/company/international-business-machines-corp",
  "inventors": [
    {
      "name": "Robert H Dennard",
      "url": "https://patentbrief.org/inventor/robert-h-dennard"
    }
  ],
  "times_cited": 191,
  "tags": [
    "semiconductors",
    "consumer_electronics",
    "computing"
  ],
  "abstract": null,
  "url": "https://patentbrief.org/patent/us/3387286/dram-memory-dennard",
  "markdown_url": "https://patentbrief.org/patent/us/3387286/dram-memory-dennard/md",
  "google_patents_url": "https://patents.google.com/patent/US3387286",
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    {
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  ]
}