Features

  • Low‑Voltage Operation:
    • AT21CS01 is self-powered via the 1.7V to 3.6V pull‑up voltage on the SI/O line
    • AT21CS11 is self-powered via the 2.7V to 4.5V pull‑up voltage on the SI/O line
  • Internally Organized as 128 x 8 (1 Kbit)
  • Temperature Range:
    • Industrial (I): -40°C to +85°C
    • Extended (E): -40°C to +125°C
  • Single-Wire Serial Interface with I2C Protocol Structure:
    • Device communication is achieved through a single I/O pin
  • Standard Speed and High-Speed Mode Options:
    • 15.4 kbps maximum bit rate in Standard Speed mode (AT21CS01 only)
    • 125 kbps maximum bit rate in High-Speed mode (AT21CS01 and AT21CS11)
  • 8‑Byte Page Write or Single Byte Writes Allowed
  • Discovery Response Feature for Quick Detection of Devices on the Bus
  • ROM Zone Support:
    • Device is segmented into four 256‑bit zones, each of which can be permanently made read‑only (ROM)
  • 256‑Bit Security Register:
    • Lower eight bytes contain a factory-programmed, read-only, 64‑bit serial number that is unique to all Microchip single‑wire devices
    • Next eight bytes are reserved for future use and will read FFh
    • Upper 16 bytes are user‑programmable and permanently lockable
  • Self‑Timed Write Cycle: 5 ms Maximum
  • Manufacturer Identification Register:
    • Device responds with unique value for Microchip as well as density and revision information
  • High Reliability:
    • Endurance: 1,000,000 write cycles
    • Data retention: 100 years
    • IEC 61000-4-2 Level 4 ESD Compliant (±8 kV Contact, ±15 kV Air Discharge)
  • Green Package Options (RoHS Compliant)
  • Die Sale Options: Wafer Form and Tape and Reel
  • AEC-Q100 Automotive Qualified