Electronic Components Datasheet Search |
|
EM4223V7WW11E Datasheet(PDF) 5 Page - EM Microelectronic - MARIN SA |
|
EM4223V7WW11E Datasheet(HTML) 5 Page - EM Microelectronic - MARIN SA |
5 / 29 page R EM4223 Copyright © 2005, EM Microelectronic-Marin SA 5 www.emmicroelectronic.com 1. GENERAL DESCRIPTION The EM4223 is a monolithic integrated circuit transponder for use in UHF passive backscatter RFID applications. Operating power for the transponder circuit is derived from the illuminating RF field of an RFID Reader by means of an on-chip virtual battery rectifier circuit. A user specified license plate or tag identifier is factory programmed into the transponder by means of laser trimming. This data is communicated to the reader by means of backscatter modulation of the illuminating RF carrier wave. The EM4223 supports both the ISO18000-6 type A and the Fast Supertag ™ (FST) Protocols. The EM4223 may be configured to wake-up in either of these modes according to user requirements. Once active, the transponder will automatically respond to either protocol (and eventually switch modes) on receipt of the appropriate commands. 2. FUNCTIONAL DESCRIPTION When a Transponder is placed in the RF energising field of a Reader it powers up. When the power supply has reached the correct operating voltage, the Configuration Register is loaded with the contents of the three pre- programmed personality flags. Depending on the state of these wake-up flags, the Transponder will be placed in either ISO 18000-6 Type A (ISO) or Fast Supertag (FST) mode and in one of three states: READY, ACTIVE or ROUND_STANDBY. After this process is complete the Transponder is able to receive commands and to transmit data to the Reader. The Transponder is half-duplex and is thus in either receive mode (default) or transmit mode. When not actively transmitting messages to the Reader on the Return Link, the Transponder will wait for the start of a new command, which will be detected as a quiet period of specific duration, followed by a valid Start Of Frame (SOF) symbol (see 54H54H Fig. 11). The Transponder requires the quiet period in order to ensure that it does not detect partial transmissions by a reader as a valid command. This can occur if a transponder enters the field of a reader and powers up part through a reader transmission. The received SOF symbol is used to calibrate the command decoder every time a command is received. This calibration is used to establish a pivot to distinguish between subsequent data ‘0’ and data ‘1’ symbols. Each time that a new command is received by the Transponder, the SOF re-calibrates the decode counter thereby compensating for any variation in the Transponder clock frequency due to changes in RF excitation levels or temperature variations. The circuit has been designed to accommodate a Transponder clock frequency variation of +/-40% from nominal. When the Transponder is transmitting the receive circuitry is disabled. All commands received from the Reader will have an immediate effect on the Transponder. In addition, certain commands will have a persistent effect. The possible immediate effects are one or both of the following: A change of State (see 55H55H Fig. 19) A Data Message sent to the Reader. The possible persistent effects are: Data Messages to the Reader will contain SUID (as described later in this section) or Data Messages to the Reader will contain USER DATA of 128 bits, The Round Size (Number of Slots) over which all of the Transponders in the population will spread their Data Messages to the Reader will be configured. The Transponder will switch between ISO and FST modes of operation (as described below). A sub-population of Transponders will be enabled to send Data Messages to the Reader dependent on either the AFI or on all or a portion of the USER DATA of 128 bits. The start of a command from the Reader has a special significance if a Transponder is operating in the FST mode and is in the ROUND_ACTIVE state. When the falling edge of the first symbol of a command (SOF) is received by a Transponder in the ROUND_ACTIVE state while in FST mode, it will immediately move to the ROUND_STANDBY state. If a command is successfully received, the Transponder will move back to the ROUND_ACTIVE state. If the Transponder does not receive a valid command it will remain in the ROUND_STANDBY state until a valid command has been received. This enables the Reader to silence all Transponders that have not already started sending their Data Messages to the Reader in compliance with the FST protocol. It is important to note that the Reader does not have to send a full command or indeed even a part of a command, as long as it sends a low going pulse of approximately ½ Tari (Type A Reference Interval Time) duration. An important feature of this transponder is its ability to switch seamlessly between ISO mode and FST mode whatever its “wake up” personality setting, depending only on the mode or characteristics of the controlling reader. A Transponder that “wakes up” in the ISO mode on power- up will switch to the FST mode if it receives a Wake_Up_FST command. Similarly, a Transponder that “wakes up” in the FST mode on power-up will switch to the ISO mode if it receives an INIT-ROUND, INIT- ROUND-ALL or BEGIN-ROUND command. |
Similar Part No. - EM4223V7WW11E |
|
Similar Description - EM4223V7WW11E |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |