AT21CS01 Single-Wire, I/O Powered Serial EEPROM with a Unique, Factory Programmed 64-bit Serial Number 1-Kbit (128 x 8) DATASHEET Features Low voltage operation Device is self-powered via 1.7V to 3.6V pull-up voltage on the SI/O line Internally organized as 128 words of 8 bits each (1-Kbit) 2 Single-Wire serial interface with I C protocol structure Device communication is achieved through a single I/O pin Standard Speed and High Speed Mode options 15.4kbps maximum bit rate in Standard Speed Mode 125kbps maximum bit rate in High Speed Mode 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 8 bytes contains a factory programmed, read-only, 64-bit Serial Number that is unique to all Atmel Single-Wire products Upper 16 bytes are user-programmable and permanently lockable Self-timed write cycle (5ms max) Manufacturer Identification support Device responds with unique value for Atmel 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 (8kV Contact, 15kV Air Discharge) Green (Lead-free/Halide-free/RoHS Compliant) package options 8-lead SOIC, 3-lead SOT23, and 4-ball Thin WLCSP Die sale options in wafer form and tape and reel Description The Atmel AT21CS01 provides 1,024 bits of Serial Electrically Erasable and Programmable Read-Only Memory (EEPROM) organized as 128 words of 8 bits each. The devices software addressing scheme allows up to eight devices to share a common Single-Wire bus. The device is optimized for use in many industrial and commercial applications where low-power and low-voltage operation are essential. Some applications examples include analog sensor calibration data storage, ink and toner printer cartridge identification, and management of after-market consumables. The device is available in space-saving package options and operates with an external pull-up voltage from 1.7V to 3.6V on the SI/O line. Atmel-8903A-SEEPROM-AT21CS01-Datasheet 082015Table of Contents 1. Pin Descriptions and Pinouts . 4 2. Device Block Diagram and System Configuration 5 2.1 Device Block Diagram . 5 2.2 System Configuration using Single-Wire Serial EEPROMs 5 3. Device Operation and Communication 6 3.1 Single-Wire Bus Transactions . 6 3.1.1 Device Reset / Power-up and Discovery Response 6 3.1.1.1 Resetting The Device 6 3.1.1.2 Device Response Upon Reset or Power-Up . 7 3.1.2 Interrupting the Device During an Active Operation 7 3.1.3 Data Input and Output Bit Frames 7 3.1.3.1 Data Input Bit Frames 8 3.1.3.2 Start / Stop Condition 9 3.1.3.3 Communication Interruptions 9 3.1.3.4 Data Output Bit Frame 10 2 4. Device Addressing and I C Protocol Emulation 11 4.1 Memory Organization 11 5. Available Opcodes . 12 5.1 EEPROM Access (Opcode Ah) . 12 5.2 Security Register Access (Opcode Bh) . 12 5.3 Lock Security Register (Opcode 2h) . 12 5.4 ROM Zone Register Access (Opcode 7h) . 12 5.5 Freeze ROM Zone State (Opcode 1h) . 12 5.6 Manufacturer ID Read (Opcode Ch) . 13 5.7 Standard Speed Mode (Opcode Dh) . 13 5.8 High Speed Mode (Opcode Eh) 13 6. Write Operations . 14 6.1 Device Behavior During Internal Write Cycle 14 6.2 Byte Write . 14 6.3 Page Write 15 6.4 Writing to the Security Register . 16 6.5 Locking the Security Register 17 6.5.1 Device Response to a Write Command on a Locked Device 17 6.5.2 Check Lock Command . 17 6.6 Setting the Device Speed . 18 6.6.1 Standard Speed Mode . 18 6.6.2 High Speed Mode . 18 2 AT21CS01 DATASHEET Atmel-8903A-SEEPROM-AT21CS01-Datasheet 082015