DATA BRIEF
For further information contact your local STMicroelectronics sales office.
Rev. 2
August 2005
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8
XRAG2
UHF, EPCglobal Class-1 Generation-2, Contactless Memory Chip
432 bit with Multi-session Protocol, Anti-collision and Kill functions
Features summary
EPCglobal Class-1 Generation-2 specification
Passive Operation (no battery required)
UHF Carrier Frequencies from 860 MHz to
960 MHz ISM Band which comply with:
North American regulations
European regulations
and other countries where similar
regulations apply
To the XRAG2:
Asynchronous 90% SSB-ASK, DSB-ASK
or PR-ASK modulation using Pulse Interval
Encoding (Up to 128 kbps)
From the XRAG2:
Backscattered reflective answers using
FM0 or Miller bit coding (up to 640 kbps)
432-bit memory with two possible
configurations:
3 memory banks: 64-bit TID, 304-bit EPC
and 64-bit RESERVED
4 memory banks: 128-bit USER, 64-bit TID,
176-bit EPC and 64-bit RESERVED
Multi-session protocol
Anti-collision functionality
Inventory, Read, Write and Erase features
Kill command
100-ms Programming Time (max) for 288-bit
programming (EPC code, Protocol Control bits
and CRC16)
More than 10,000 Write/Erase cycles
Over 40 Year Data Retention
Figure 1.
Delivery forms
Unsawn unbumped wafers
or
sawn and bumped wafers
www.st.com
1 Summary description
XRAG2
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1 Summary
description
The XRAG2 is a full-featured, low-cost integrated circuit for use in Radio Frequency
Identification (RFID) transponders (tags) operating at UHF frequencies. It is a 432-bit memory
organized in 16-bit Words in 3 or 4 memory banks as shown in
Figure 3
and
Figure 4
.
When connected to an antenna, the operating power is derived from RF energy produced by
the RFID reader. Incoming data are demodulated and decoded from the received Double-Side
Band Amplitude Shift Keying (DSB-ASK), Single-Side Band Amplitude Shift Keying (SSB-ASK)
or Phase-Reversal Amplitude Shift Keying modulation signal. Outgoing data are generated by
antenna reflectivity variations using either the FM0 or Miller bit coding principle (RFID reader
parameter).
A Kill function is provided to permanently disable the tag.
Anti-collision features enable the rapid inventorying of tag populations.
Communication between reader and tag are Half-duplex meaning that tags do not decode
reader commands while backscattering.
The data transfer rate is defined by the local UHF frequency regulations.
The XRAG2 is fully compliant with the ePC Global Class-1 Generation-2 UHF RFID
specification (Revision 1.0.9) for the radio-frequency power and signal interface.
The reader and the XRAG2 dialog through the following consecutive operations known as RTF
(Reader Talk First) communication:
Activation of the XRAG2 by the UHF operating field of the reader
Transmission of a command by the reader
Transmission of a response by the XRAG2
Table 1.
Signal names
The XRAG2 is specifically designed for extended range applications that need automatic item
identification. The XRAG2 provides a fast and flexible anti-collision protocol that is robust in
noisy and unpredictable RF conditions typical of RFID applications. The XRAG2 EEPROM
memory can be read and write which enable users to program the EPC code and USER
memory at the point of application, if desired.
Figure 2.
Pad connections
AC1
Antenna Pad
AC0
Antenna Pad (GND)
memory
Power
Supply
Regulator
Demodulator
ASK
Reflecting
Modulator
EEPROM
AC1
AC0
432-bit
XRAG2
2 XRAG2 memory mapping
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2
XRAG2 memory mapping
The XRAG2 is a 432-bit memory divided into a 3-memory bank (without USER memory) or
4-memory bank (with USER memory) configuration. Each bank is organized into 16-bit Words.
The reader can read part or all of each memory bank in single or multiple groups of 16-bit
Words. Use the WRITE command to write to device memory using 16-bit Words. The
BLOCKWRITE command enables readers to write up to four 16-bit Words to device memory at
a single time. Erase multiple 16-bit Words (up to the complete memory bank) using the
BLOCKERASE command.
Note:
The 64-bit TID memory content is written by STMicroelectronics during the manufacturing
process in compliance with the ISO 15963 Technical Report in order to comply with ISO 18000
recommendations.
Figure 3
describes the three-memory bank configuration.
Table 2.
Memory bank description
Memory Bank
Description
USER
User-specific data
TID (Tag-identification Data)
Manufacturer and custom information
EPC (Electronic Product Code)
CRC-16, Protocol Control and item identification code (EPC)
RESERVED
Kill and access passwords
Figure 3.
Three-memory bank configuration
TID Bank
RESERVED Bank
EPC Bank
64-bit
304-bit
64-bit
TID
TID
TID
TID = E002h
30h
20h
10h
00h
3Fh
2Fh
1Fh
0Fh
Access Password
Access Password
Kill Password
Kill Password
30h
20h
10h
00h
3Fh
2Fh
1Fh
0Fh
RFU
EPC
...
up to 256 EPC bit
120h
110h
...
...
12Fh
11Fh
...
...
...
EPC
(PC+EPC) length
CRC16
...
20h
10h
00h
...
2Fh
1Fh
0Fh
AFI/NSI
Bank 10
Bank 01
Bank 00
2 XRAG2 memory mapping
XRAG2
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The four-memory bank configuration is shown in
Figure 4
.
Figure 4.
Four-memory bank configuration
TID Bank
USER Bank
RESERVED Bank
EPC Bank
128-bit
64-bit
176-bit
64-bit
TID
TID
TID
TID = E002h
30h
20h
10h
00h
3Fh
2Fh
1Fh
0Fh
Access Password
Access Password
Kill Password
Kill Password
30h
20h
10h
00h
3Fh
2Fh
1Fh
0Fh
DSFID
EPC
...
up to 128 EPC bit
A0h
90h
...
...
AFh
9Fh
...
...
...
EPC
(PC+EPC) length
CRC16
...
20h
10h
00h
...
2Fh
1Fh
0Fh
AFI/NSI
User
...
User
User
70h
...
10h
00h
7Fh
...
1Fh
0Fh
Bank 10
Bank 01
Bank 00
Bank 11
XRAG2
3 XRAG2 commands
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3 XRAG2
commands
The XRAG2 offers Select, Inventory, and Access commands sets supported as defined in
ePCglobal Class-1 Generation-2 UHF RFID specifications (Revision 1.0.9).
Table 3.
XRAG2 commands
Command Set
Available Commands
Select Command Set
SELECT
Inventory Command Set
QUERY, QUERYADJUST, QUERYREP, ACK and NAK
Access Command Set
REQ_RN, READ, WRITE, KILL, LOCK, ACCESS, BLOCKWRITE and
BLOCKERASE
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