General Description
The DS28E10 combines secure challenge-and-response authentication  functionality  based  on  the  FIPS  180-3 specified Secure Hash Algorithm (SHA-1) with 224 bits of  one-time  programmable  user  EPROM  in  a  single chip.  Once  written,  the  memory  is  automatically  write protected.  Additionally, each device has its own guaran teed unique 64-bit ROM identification number (ROM ID)
that is factory programmed into the chip. Memory writes

FEATUREs
Dedicated Hardware-Accelerated SHA-1 Engine for Generating SHA-1 MACs
One Page of 28 Bytes User OTP EPROM
Irreversible Write Protection
Unique, Factory-Programmed 64-Bit Identification Number
1-Wire Interface for Standard and Overdrive Speed
Communicates with Host at Up to 15.4kbps at Standard Speed or Up to 125kbps in Overdrive Mode
Operating Range from 2.8V to 3.6V, -40NC to +85NC
3-Lead SOT23, 6-Lead TSOC Package
±6kV Human Body Model (HBM) ESD Protection (typ) on 1-Wire and VCCPin