AT21CS01/AT21CS11
Single-Wire, I/O Powered 1-Kbit (128 x 8) Serial EEPROM
with a Unique, Factory-Programmed 64-Bit Serial Number
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 K-bit)
• Industrial Temperature Range: -40°C to +85°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 contains 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 (Lead-free/Halide-free/RoHS Compliant) Package Options
• Die Sale Options: Wafer Form and Tape and Reel
Packages
• 2-pad XSFN, 3-lead SOT23, 8-lead SOIC and 4-ball WLCSP
DS20005857B-page 1
Datasheet
© 2019 Microchip Technology Inc.