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em4469 copyright 2003, em microelectronic-marin sa 1 www.emmicroelectronic.com 512 bit read/write contactless identification device description em4469 is a cmos integrated circuit intended for use in electronic read/write rf transponders. the ic is powered by picking the energy from a continuous 125 khz magnetic field via an external coil, which together with the integrated capacitor form a resonant circuit. the ic read out data from its internal eeprom and sends it out by switching on and off a resistive load in parallel to the coil. commands and eeprom data updates can be executed by 100% am modulation of the 125 khz magnetic field. there are several data rate and data encoding options available. options are stored in eeprom configuration word. read and write access to eeprom can be protected by 32 bit password. all eeprom words can be write protected by setting lock bits which transform them in read-only. it contains factory programmed and locked 32 bit uid number, chip type and customer code. features 512 bit eeprom organised in 16 words of 32 bits 32 bit password read and write protection 32 bit unique identification number (uid) 10 bit customer code lock feature convert eeprom words in read only multi-purpose encoding (manchester, biphase, miller, psk, fsk) multi-purpose data rate from 1 up to 32 kbaud power-check for eeprom write operation 100 to 150 khz frequency range on-chip rectifier and voltage limiter no external supply buffer capacitor needed -40 to +85 c temperature range very low power consumption em4469: trimmed resonant capacitor integrated on chip (330pf, 250pf or 75pf mask option) applications access control animal identification material logistics typical operating configuration fig. 1 em microelectronic - marin sa c1 em4469 l c2
em4469 copyright 2003, em microelectronic-marin sa 2 www.emmicroelectronic.com absolute maximum ratings v ss = 0v parameter symbol conditions input current on coil1/coil2 i coil -30 to +30ma operating temperature range t op -40 to +85c storage temperature range t store -55 to +125c electrostatic discharge to mil-std-883c method 3015 v esd 2000v table 1 stresses above these listed maximum ratings may cause permanent damages to the device. exposure beyond specified operating conditions may affect device reliability or cause malfunction. handling procedures this device has built-in protection against high static voltages or electric fields. however due to the unique properties of this device, anti-static precautions should be taken as for any other cmos component. unless otherwise specified, proper operation can only occur when all terminal voltages are kept within the supply voltage range. operating conditions v ss = 0v parameter symbol min. typ. max. units operating temperature ac voltage on coil pins maximum coil current frequency on coil pins t op v coil1 i coil1 f coil1 -40 -10 100 +25 125 +85 * 10 150 c v pp ma khz table 2 *) maximum voltage is defined by forcing 10ma on coil1 ? coil2 electrical characteristics v pos = 2.0 v, v ss = 0 v, f coil1 = 125 khz square wave, v coil1 = 4v pp , t op = 25c, unless otherwise specified parameter symbol conditions min. typ. max. unit supply current in read mode i rd 1.8 3.0 m a (note 1) supply current write mode i wr 25 40 m a modulator on voltage drop v on1 i ( coil2 - coil1 ) = 100 m a i ( coil2 - coil1 ) = 5ma 2.2 2.4 2.8 3.2 v v limiter por level v lim v por i ( coil2 - coil1 ) = 10ma rising edge 8 1.3 v v clock extractor input min. v coil1 1.4 v pp resonance capacitor c r 330 pf option 320 330 340 pf (note 3) 250 pf option 245 250 255 pf (note 3) 75 pf option 70 75 80 pf (note 3) eeprom data retention t ret t op = 55c 10 years (note 2) eeprom write cycles n cy v po s = 3.0 v 100000 cycles table 3 note 1: data rate f rf /64, manchester code note 2: based on 1000 hours at 150c. note 3: applies only on em4469 device timing characteristics v pos = 2.0 v, v ss = 0 v, f coil1 = 125 khz square wave, v coil1 = 4v pp , t op = 25c, data rate f rf /64, manchester code unless otherwise specified parameter symbol conditions min. typ. max. unit data extractor timeout t mono 20 30 40 m s eeprom programming time t wee 6.7 ms power check time t pc 512 m s initalisation after write word t ini 928 m s power-up initialisation t pu 2.5 3.0 ms processing pause t pp 544 m s table 4
em4469 copyright 2003, em microelectronic-marin sa 3 www.emmicroelectronic.com block diagram fig. 2 functional description the ic builds its power supply through an integrated rectifier. when it is placed in a magnetic field the dc internal voltage starts to increase. as long the power supply is lower than the power on reset (por) threshold, the circuit is in reset mode to prevent unreliable operation. in this mode the modulator is off. after the supply voltage cross the por threshold, the circuit reads configuration word and then enters in default read mode according to configuration just read. during the configuration word readout the modulator is also off. while the ic is operating in default read mode it checks the coil signal to detect eventual command from reader. in the case reader field stops for a period longer then t mono it interrupts read mode and expects reader to send the command. in the case a valid command pattern is detected the command is executed. after execution of command the default read mode is entered. block description power supply this block integrates an ac/dc converter, which extracts the dc power from the incident rf field. it will also acts as limiter, which clamps the voltage on coil terminals to avoid chip destruction in strong rf fields. power on reset (por) when the em4469 with its attached coil enters an electromagnetic field, the built in ac/dc converter will supply the chip. the dc voltage is monitored and a reset signal is generated to initialise the logic. the power on reset is also provided in order to make sure that the chip will start issuing correct data. hysteresis is provided to avoid improper operation at the limit level. vpor t reset vdd t hysteresis em4469 active fig. 3 clock extractor the clock extractor will generate a system clock with a frequency corresponding to the frequency of the rf field ( f rf ). the system clock is used by a sequencer to generate all internal timings. data extractor the transceiver generated field will be amplitude modulated (field stops) to transmit data to the em4469. the data extractor detects absence of signal on coil terminals for period longer then t mono . modulator the data modulator is driven by logic. when modulator is switched on it will draw a large current from both coil terminals, thus amplitude modulating the rf field. power check this block is used to check whether there is enough power available to securely write eeprom. modulator logic eeprom clock extractor data extractor v pos v ss power supply reset power on reset coil1 c r c buf coil2 power check
em4469 copyright 2003, em microelectronic-marin sa 4 www.emmicroelectronic.com logic logic is composed of several sub-blocks, which are described in the following text. controller controller controls the state of the ic. its main states are power off (power supply below por level), power-up initialisation, default read, command processing and disabled state. configuration register at power-up when power supply level gets higher the por threshold the content of eeprom configuration word is transferred in configuration register to define default operating mode of the ic. sequencer it gets clock signal from clock extractor and generates data rate clock and other timing signals needed for operation of other blocks. data rate is defined by number ?n? stored in configuration word. encoder encoder encodes serial nrz data before it is transmitted to modulator. it has several options implemented to give different codes, which are frequently used in rfid (manchester, biphase, miller, psk, fsk). command decoder command decoder observes output of data extractor. when a field stop is detected it puts controller in command processing state and starts to decode data coming in. fig.4 eeprom organisation the 512 bits of eeprom are organised in 16 words of 32 bits. the eeprom words are numbered from 0 to 15, bits in a word are numbered from 0 to 31. the lsb first principle is always respected. the 32 bits of eeprom word are programmed with one write word command. the first two words are factory programmed read only words (words 0 and 1). they are assigned to chip type, chip version, customer code and unique identification number (uid). the next three words (words 2 to 4) are used to define device operation options (housekeeping words). they consist of password word, protection word and configuration word. words 5 to 15 are user free (352 user free bits). addr. ( dec) description type b 0 ,.. ..,b 31 0 chip type, resonant cap., customer code ro ct 0 - ct 31 1 uid ro uid 0 - uid 31 2 password wo ps 0 - ps 31 3 protection word otp pr 0 - pr 31 4 configuration word rw co 0 - co 31 5 user free rw us 0 - us 31 6 user free rw us 0 - us 31 7 user free rw us 0 - us 31 8 user free rw us 0 - us 31 9 user free rw us 0 - us 31 10 user free rw us 0 - us 31 11 user free rw us 0 - us 31 12 user free rw us 0 - us 31 13 user free rw us 0 - us 31 14 user free rw us 0 - us 31 15 user free rw us 0 - us 31 encoder controller command decoder sequencer configuration register clock extractor eeprom data extractor from from from eeprom to modulator to to all blocks
em4469 copyright 2003, em microelectronic-marin sa 5 www.emmicroelectronic.com word types: rw: reading and writing poss ible ro: read only, changing content of this word is not possible wo: write only, reading of this word is not possible otp: bits of this word are one time programmable chip type is a fix 4 bit number indicating member of the compatible family of chips. resonant capacitor is a fix 2 bit number indicating the value of integrated resonant capacitor. customer code is a 10 bit fixed code attributed to a customer. the other bits of word 0 are reserved for future use. word 1 contains 32 bit unique identification number (uid), which can not be changed by user. the 32 bit password word has to be sent in login command to enable password protected operations. the password word can not be read out by read word command. the protection word protects eeprom words from being written. every eeprom word is protected by a pair of bits in protection word. once this bit pair is set to 11 the word cannot be written (it becomes read-only). the configuration word defines operating options: data rate, encoder, last default read word (lwr), use of password and some other options are defined in this word. organisation of word 0 chip type bits ct 1 to ct 4 of word 0 are indicating member of the compatible family of chips. ct 1 ,..ct 4 chip type 0100 em4469 resonant capacitor bits ct 5 and ct 6 are used to indicate resonant capacitor value. ct 5 ,ct 6 resonant cap 00 no resonant capacitor 10 75 pf 01 250 pf 11 330 pf customer code bits ct 9 to ct 18 are attributed to customer code. every customer can ask to get its own customer code. default customer code is 1000000000, where the leftmost bit is ct 9. bits ct 0, ct 7, ct 8 and ct 19 - ct 31 are reserved for future use and are set to 0. organisation of configuration word configuration word is used to define device operating mode. co 0 ? co 5: data rate bits co 0 ? co 5 define a binary number ?n? where co 0 is lsb and co 5 is msb. data rate is defined as f rf /2(n+1), where n 3 1. the lowest data possible is therefore f rf /128 and the highest f rf /4. co 6 ? co 9: encoder co 6 ? co 9 encoder 0000 no encoding (nrz) 1000 manchester 0100 biphase 1100 miller 1010 psk2 0110 psk3 0001 fsk other not used co 10 , co 11: psk carrier frequency co 10 , co 11 psk cf 00 f rf /2 10 f rf /4 01 f rf /8 11 not used co 12 , co 13: not used co 14 - co 17 last default read word (lwr) bits co 14 - co 17 contain the binary word address of last word read in default read. co 17 is msb and co 14 is lsb. please note that valid range is only from 5 to 15. co 18 : read login in case this bit is set to logic 1 the reading of all words except ro words 0 and 1 by using read word command is protected. in order to read any of these words using read word command a login flag has to be set. co 19 : read housekeeping login in case this bit is set to logic 1 the reading of all housekeeping words by using read word command is protected. in order to read any housekeeping word using read word command a login flag has to be set. of course password (word 2) can not be read since reading of this word is never possible.
em4469 copyright 2003, em microelectronic-marin sa 6 www.emmicroelectronic.com co 20 : write login in case this bit is set to logic 1 the eeprom programming by using write word command is protected. in order to write any word using write word command a login flag has to be set. co 21 : write housekeeping login in case this bit is set to logic 1 the programming of housekeeping words by using write word command is protected. in order to write any housekeeping word using write word command a login flag has to be set. please note that writing to password word is always protected by password. co 22 : read after write in the case this bit is set to logic 1 the word just written by write word command is read before em4469 transitions back in default read mode. please note that since reading from password word is not possible this is the only possibility to read back the password just written. co 23 : disable in case this bit is set to logic 1 disable command is accepted. co 24 : rtf in case this bit is set to logic 1 there is no modulation in default read, em4469 operates in reader talk first (rtf) mode. in this mode communication is done only using commands. co 25 - co 31: reserved for future use organisation of protection word the protection word protects eeprom words from being written. the bits in protection word are one time programmable (otp) which means that once they have been set to 1 they can not be reset to 0 any more. every eeprom word is protected by a bit pair in protection word. state 00 of the pair means that the word is not protected, state 11 means write protection. 01 and 10 states are not allowed. due to the otp feature of bits in protection word a word once protected becomes read only and can not be reverted back to rw. please note that it is possible to protect the protection word itself, in that case the protection system is locked and cannot be changed any more. bit pr 0 pr 1 pr 2 pr 3 pr 30 pr 31 word w 0 w 1 w 15 table above presents the location of bit pair protecting a certain word. bits pr 0 and pr 1 protect word 0 , bits pr 2 and pr 3 word 1 and so on. the protection bits of ro words 0 and 1 are already factory programmed to 1. eeprom delivery state as already mentioned above, in all cases the words 0 and 1 are factory programmed and locked. in the case a customer code is attributed, the content of other words can be personalised according to customer wish. in case of default configuration with customer code 1 password, configuration word and user free words are all set to 0, the protection bits of ro words 0 and 1 are of course factory programmed to 1, other protection bits are also set to 0. register name lsb .. ..msb comments customer code 1000000000 data rate 011111 rf/64 (2kbaud) encoder 1000 manchester psk carrier frequency 00 f rf /2 (not used in this case) last default read word 1111 last word read is at address 15 read login 0 no login required read housekeeping login 0 no login required write login 0 no login required write housekeeping login 0 no login required read after write 0 no read after write disable 0 disable command is not accepted rtf 0 ttf mode (modulation active) all reserved and unused bits 0 default read after the supply voltage crosses the por threshold, the circuit enters power-up initialisation in which it reads configuration word and then transitions in default read mode according to configuration just read. in default read mode the chip will continuously send data starting from word 5 and finishing with word lwr. after sending last bit (31) of word lwr readout continues without interruption with first bit of word 5. in the case word 5 is set as lwr only word 5 is repeated. forward link communication (reader to tag) as already mentioned commands can be send from reader to tag by initiating a command while chip is in default read. the communication is done by using 100% modulation of reader field (also called field stops or ook). the first field stop initialise command mode. since it can happen while modulator switch is off it needs to be long enough to stop oscillation on coil terminals for at least t mono .
em4469 copyright 2003, em microelectronic-marin sa 7 www.emmicroelectronic.com em4050 code (figure 5) at reception of the first field stop, the chip stops immediately the reading and expects then another bit "0" to switch to receive mode. the transceiver and the chip are now synchronised and further data is sent with a bit rate of 32 periods of the rf field. the em4469 turns "on" its modulator at the beginning of each frame of 32 clock periods corresponding to one bit. to send a logic "1" bit, the transceiver continues to send clocks without modulation. after 16 clocks, the modulation device of is turned "off" allowing recharge of the internal supply capacitor. to send a logic "0" bit, the transceiver stops sending clocks (100% modulation) during the first half of a bit period (first 16 periods with modulation device on). in order to correctly detect the field "off" the transceiver must wait that modulation device switch on before turning "off" the field. it is recommended to turn "off" the field after 4 clocks of the bit period, the minimum requirement is 1. in the recommended case the field is stopped from clock 5 to 16 of the bit period, and then turned "on" again for the remaining 16 periods. while the transceiver is sending data to the transponder, two different modulations will be observed on both coils. during the first 16 clocks of a bit period, the em4469 is switching "on" its modulation device causing a modulation of the rf field. this modulation can also be observed on the transceiver's coil. to send a bit "0" the transceiver will switch "off" the field, and this 100% modulation will be observed on the transponder coil. transceiver coil transponder coil "1" "1" "1" "0" "0" "0" 16 16 periods of rf field (opt 32): bit period data : modulation induced by the transceiver modulation induced by the transponder 16 * * recommended minimum : 7/4 periods (opt64/opt32) 16 periods of rf field (opt 64): 32 32 32 32 : 1 period opt64 is the chip option with a bit period corresponding to 64 priods of the rf field opt32 is the chip option with a bit period corresponding to 32 priods of the rf field fig.5 commands command structure: all commands start by 3 bit command code, followed by command arguments. possible command arguments are a word address and a 32 bit data field. the 3 bit command code is terminated by an even parity bit. the address field contains 4 bit address, two bits at 0 reserved for future extension and an even parity bit. the 32 bit data field has an even parity bit inserted every 8 data bits , data is terminated with 8 column parity bits and a 0. the figures below represent the organisation of command fields.
em4469 copyright 2003, em microelectronic-marin sa 8 www.emmicroelectronic.com command code structure : cc 0 cc 1 cc 2 p address structure: a 0 a 1 a 2 a 3 "0" "0" p data structure: d 0 d 1 d 2 d 3 d 4 d 5 d 6 d 7 p 0 d 8 d 9 d 10 d 11 d 12 d 13 d 14 d 15 p 1 d 16 d 17 d 18 d 19 d 20 d 21 d 22 d 23 p 2 d 24 d 25 d 26 d 27 d 28 d 29 d 30 d 31 p 3 pc 0 pc 1 pc 2 pc 3 pc 4 pc 5 pc 6 pc 7 "0" there are four commands implemented: login, write word, read word and disable. cc 0 - cc 2 p command 001 1 login 010 1 write word 100 1 read word 101 0 disable login command sending login command is necessary before sending any password protected command. in login command a 32 bit password including parity bits is sent as command parameter. the 32 bit password is sent according to data structure defined above (45 bits including parity). in the case the parity bits are correct and 32 bit password sent matches with content of word 2 a login flag is set. login flag is set until next power-up, which means that login command has to be sent only once after power up to enable execution of password protected commands. in case login command is successfully processed ic responds with preamble pattern (00001010) and returns in default read mode. in case the login is not accepted (wrong password or error in parity) a pattern 00000001 is sent and ic returns in default read mode. write word command in write word command first the 4 bit word address is sent followed by 32 bit data. in the case command is correctly processed ic first checks if the login flag is set (for the case writing is password protected), if addressed word is not write protected and if there is enough power to write eeprom. in case all these conditions are fulfilled and there is no parity error eeprom is written. after eeprom is written the configuration word is reloaded from eeprom, a preamble pattern (00001010) is sent and chip returns in default read mode. loading of configuration word is useful for the case the configuration word has just been changed so that new settings are loaded. in the case a read-after-write bit is set the word just written is sent after the preamble pattern. response is equivalent to the response of read word command. in case the write word command is not accepted (error in parity or at least one of the checks failed) a pattern 00000001 is sent and ic returns in default read mode. read word command in read word command the four bit word address is sent as command parameter. in the case command is correctly processed ic first checks if the login flag is set in the case reading is password protected. in case readout is authorised a preamble pattern (00001010) followed by content of 32 bit word is sent. please note that the 32 bit data is sent in command data structure format (45 bits including parity bits) which is not the same as in default read where only the data from eeprom is read. in case the read word command is not accepted (parity error, password protection or reading from address 2) a pattern 00000001 is sent and ic returns in default read mode. disable command disable command is accepted in the case disable bit of configuration word is set to 1. in disable command an all-1 data field is sent as command parameter (45 bits including parity bits, where parity bits are all 0). command structure is therefore similar to login command. when this command is detected chip stops all operations until next power-up. in case the disable command is not accepted (disable bit set to 0, parity error or some other data then all-1) a pattern 00000001 is sent and ic returns in default read mode. error during command detection in case a command code which is not supported or a command parity bit error are detected the ic exits command processing and returns in default read mode without sending any message.
em4469 copyright 2003, em microelectronic-marin sa 9 www.emmicroelectronic.com login em4469 default read preamble default read reader "0011" password timings t pp write word em4469 default read preamble default read reader "0101" address data timings t pc t wee t ini read word em4469 default read preamble read word default read reader "1001" address timings t pp disable em4469 default read disabled mode reader "1010" "all1" data timings return link encoder (tag to reader) as described before the nrz data coming from eeprom pass in read mode (default read or answer to read word command) through encoder before it is transferred to modulator. the logic 1 (high) means modulator is on. manchester code: in manchester coding there is a transition from high to low or from low to high in the middle of bit period. when logic 0 is transmitted first half of bit period the output is low and second half of bit period it is high. when logic 1 is transmitted first half of bit period the output is high and second half of bit period it is low. biphase code in biphase coding there is a transition from high to low or from low to high at the beginning of each bit period. in the case logic 0 is transmitted there is additional transition in the middle of bit period. in case logic 1 is transmitted there is no transition in the middle of bit period. nrz in manchester biphase miller code advantage of miller code is that minimum pulse duration is one bit period. see figure below for example of miller code. in the case logic 1 is transmitted there is a transition in middle of bit period. in case a single 0 is transmitted there is no transition, in case of more zeros there are transitions in beginning of bit period starting with second zero. 1 1 1 1 1 1 0 0 0 0 0 nrz miller psk codes there are two types of psk codes implemented. the psk subcarrier frequency can also be defined (rf/2, rf/4 and rf/8 are implemented). for correct operation of psk codes the selected data rate has to be an integer multiple of psk subcarrier frequency. psk2: phase change on bit clock when input high psk3 : phase change on rising edge of input fsk code: in case logic 0 is present on the input a signal with frequency f rf /5 is transmitted to output. in case logic 1 is present on the input a signal with frequency f rf /8 is transmitted to output. code logic 1 logic 0 fsk f rf /8 f rf /5 examples of settings em h4001, h4002, h4100 ver. 01: data rate: f rf /64 encoder: manchester lwr: 6 (64 bits) iso11785 fdx-b data rate: f rf /32 encoder: biphase lwr: 8 (128 bits)
em4469 copyright 2003, em microelectronic-marin sa 10 www.emmicroelectronic.com package information dimensions of pcb and cid version fig. 6 fig. 7 pad location em4469 all dimensions in m m y x 1025 1472 154 668 140 717 pad size : 86 x 86 481 1110 213 1 2 3 4 5 6 fig. 8 pad description pad name function 1 coil 1 coil connection 1 2 vpos internal supply voltage 3 test_o test output 4 test_i test input 5 vss internal supply ground 6 coil 2 coil connection 2 f f g c2 c1 marking area d a b e j k front view top view r y x z symbol min typ max x 8.0 y 4.0 z 1.0 dimensions are in mm dimensions are in mm cid package pcb package c2 c1 symbol min typ max a 8.2 8.5 8.8 b 3.8 4.0 4.2 d 5.8 6.0 6.2 e 0.38 0.5 0.62 f 1.25 1.3 1.35 g 0.3 0.4 0.5 j 0.42 0.44 0.46 k 0.115 0.127 0.139 r 0.4 0.5 0.6
em4469 copyright 2003, em microelectronic-marin sa 11 www.emmicroelectronic.com ordering information theses charts shows general offering ; for detailed part number to order, please see the table ?standard versions? below. die form - circuit nb: customer version: em4469 %%% = only for custom specific version version: v0 = no resonant capacitor v1 = 75 pf resonant capacitor v2 = 250 pf resonant capacitor v3 = 330 pf resonant capacitor die form: thickness: ww = wafer 6 = 6 mils (152um) ws = sawn wafer/frame 7 = 7 mils (178um) wt = sticky tape 11 = 11 mils (280um) 27 = 27 mils (686um) %%% em4469 v3 ws 11 packaged devices - circuit nb: customer version: em4469 %%% = only for custom specific version version: v0 = no resonant capacitor v1 = 75 pf resonant capacitor v2 = 250 pf resonant capacitor v3 = 330 pf resonant capacitor package/card & delivery form: ci2lb = cid pack, 2 long pins (2.5mm), in tape ci2lc = cid pack, 2 long pins (2.5mm), in bulk cb2rc = pcb package, 2 pins, in bulk ci2lc %%% em4469 v3 remarks: for ordering please use table of ?standard version? table below. for specifications of delivery form, including gold bumps, tape and bulk, as well as possible other delivery form or packages, please contact em microelectronic-marin s.a. standard versions & samples: for samples please order exclusively: part number capacitor option package delivery form em4469 v3ci2lc 330pf cid package, 2 pins (length 2.5mm) bulk em4469 v3cb2rc 330pf pcb package, 2 pins bulk the versions below are considered standards and should be readily available. for other versions or other delivery form, please contact em microelectronic-marin s.a. part number capacitor option package/die form delivery form em4469 v3cb2rc 330pf pcb package, 2 pins bulk em4469 v3ci2lc 330pf cid package, 2 pins (length 2.5mm) bulk em4469 v3ci2lb 330pf cid package, 2 pins (length 2.5mm) tape em4469 vxyyy-%%% custom custom em microelectronic-marin sa cannot assume responsibility for use of any circuitry described other than circuitry entirely embodied in an em microelectronic-marin sa product. em microelectronic-marin sa reserves the right to change the circuitry and specifications without notice at any time. you are strongly urged to ensure that the information given has not been superseded by a more up-to-date version. ? em microelectronic-marin sa, 06/03, rev. a/prelim.

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