GENERAL DESCRIPTION
The DS28EC20 is a 20480-bit, 1-Wire® EEPROM organized as 80 memory pages of 256 bits each. An additional page is set aside for control functions. Data is written to a 32-byte scratchpad, verified, and then copied to the EEPROM memory. As a special feature, blocks of eight memory pages can be write protected or put in EPROM-Emulation mode, where bits can only be changed from a 1 to a 0 state. The DS28EC20 communicates over the single-conductor 1-Wire bus. The communication follows the standard1-Wire protocol. Each device has its own unalterableand unique 64-bit ROM registration number. Theregistration number is used to address the device ina multidrop 1-Wire net environment.

FEATURES
20480 Bits of Nonvolatile (NV) EEPROMPartitioned into Eighty 256-Bit Pages
Individual 8-Page Groups of Memory Pages(Blocks) Can Be Permanently Write Protected orPut in OTP EPROM-Emulation Mode ("Write to 0")
Read and Write Access Highly Backward-Compatible to Legacy Devices (e.g., DS2433)
256-Bit Scratchpad with Strict Read/WriteProtocols Ensures Integrity of Data Transfer
200k Write/Erase Cycle Endurance at +25°C
Unique, Factory-Programmed, 64-BitRegistration Number Ensures Error-Free DeviceSelection and Absolute Part Identity
Switchpoint Hysteresis and Filtering to OptimizePerformance in the Presence of Noise
Communicates to Host at 15.4kbps or 90kbpsUsing 1-Wire Protocol
Low-Cost TO-92 Package
Operating Range: 4V to 5.25V, -40°C to +85°C
Operating Range: 3.135V to 3.465V,0°C to +70°C
Enhanced ESD Protection

APPLICATIONS
Device Authentication
IEEE 1451.4 Sensor TEDS
Ink/Toner Cartridges
Medical Sensors
PCB Identification
Wireless Base Stations