INTEGRATED CIRCUITS DATA SHEET HTCM400 HITAG core module hardware Product specification Supersedes data of 1999 Jan 01 File under Integrated Circuits, IC11 2001 Oct 04 Philips Semiconductors Product specification HITAG core module hardware HTCM400 CONTENTS 1 FEATURES 2 APPLICATIONS 3 GENERAL DESCRIPTION 4 ORDERING INFORMATION 5 BLOCK DIAGRAM 6 PINNING 7 FUNCTIONAL DESCRIPTION 7.1 7.1.1 7.1.2 7.1.3 7.1.4 7.1.5 7.2 7.3 7.3.1 7.3.2 7.3.3 7.3.4 7.3.5 7.3.6 7.3.7 System overview Transponders Host system I/O functions Connecting the antenna Behaviour with several transponders Core module software Core module hardware EEPROM Microcontroller Interface: microcontroller - host Transmitter and receiver Antenna HITAG long range reader module Interface: microcontroller - HITAG long range board Postal approval Common mode filtering Filtering of the supply voltages Filtering of the antenna circuit ESD protection Security considerations Data reliability CRC of a data stream between reader module and transponder Checking user data Data privacy Operating security Anticollision mode Monitoring the supply voltage Antenna rupture or short-circuit 7.4 7.4.1 7.4.2 7.4.3 7.4.4 7.5 7.6 7.6.1 7.6.2 7.6.3 7.7 7.7.1 7.7.2 7.7.3 2001 Oct 04 8 ELECTRICAL SPECIFICATIONS 9 MECHANICAL SPECIFICATIONS 9.1 9.2 Mounting the module Dimensions 10 APPLICATION INFORMATION 10.1 10.2 10.3 10.3.1 Metallic environment, interferences Distance between two antennas To build a proximity reader Connection of the HTCM400 in order to build a proximity read and write device. Power supply Interface driver I/O functions To build a long range reader Possible sources of errors by connecting the HTCM400 10.3.2 10.3.3 10.3.4 10.4 10.5 2 11 INSTRUCTIONS FOR BUILDING HITAG PROXIMITY ANTENNAS 11.1 11.2 11.3 11.4 11.5 11.6 11.7 11.8 11.9 Basics Antenna coil Measuring the inductance Antenna cable length Antenna tuning Determining the serial resistance of the antenna Checking the antenna voltage VL Procedure for practical antenna design Reference antennas 12 SURVEY OF REFERENCED DOCUMENTS 13 DATA SHEET STATUS 14 DEFINITIONS 15 DISCLAIMERS Philips Semiconductors Product specification HITAG core module hardware 1 HTCM400 FEATURES • Compact size • Communication with all HITAG transponders and various other 125 kHZ transponders • Data encryption, key handling Nevertheless, the proximity application also prevents any type of malfunction even if several transponders arrive in the communication field of the antenna at the same time. • Fast and easy system integration • Serial CMOS interface • Meets all requirements for CE and EMI approval. The HITAG product family is used both in the proximity area (operating range up to approximately 200 mm) and in the long range area (operating range to approximately 1000 mm). 2 In both cases the HITAG core module forms the central part as illustrated in Figs 9 and 11. • Simple antenna design • 5 V power supply voltage APPLICATIONS • HITAG proximity readers The HITAG core module provides you with a universal, cost-effective and small module. The use of modular architecture guarantees versatile usability and easy integration into bigger systems. The HITAG core module enables communication with HITAG 1 and HITAG 2 transponders. • HITAG long range readers. 3 GENERAL DESCRIPTION HITAG(1) is the name of one of the universal and powerful product lines of our 125 kHz family. The contactless read/write system that works with passive transponders is suitable for various applications. Inductive coupling helps you to achieve operating distances up to 1000 mm and the use of cryptography guarantees highest data security. Easy integration and application of the HITAG core module is due to: • Small size • Uncomplicated interfaces. Based on the core module delivered by Philips and using only a few additional components, every client can build his individually designed proximity reader without difficulty. Moreover, you can obtain the long range reader module HTRM800 (with an additional high frequency component) from Philips, if long range applications are required. Anticollision mode, which is used only in long range operation, allows you to handle several transponders that are within the communication field of the antenna at the same time, thus achieving highest operating security and permitting to handle several data transfers quickly and simultaneously. In this context anticollision becomes an essential element of applications such as ski-ticketing and long range access control. With applications of that type it will always happen that several transponders arrive in the communication field of the antenna at the same time. (1) HITAG - is a trademark of Philips Semiconductors Gratkorn GmbH. 4 ORDERING INFORMATION PART NUMBER HTCM400/EAE 2001 Oct 04 NAME HITAG core module 3 ORDER CODE (12NC) 9352 339 00122 Philips Semiconductors Product specification HITAG core module hardware 5 HTCM400 BLOCK DIAGRAM handbook, full pagewidth power supply EEPROM MEMORY R1 antenna TRANSMITTER C I/O functions MICROCONTROLLER R2 (1) RECEIVER L CORE MODULE HTCM400 host system MGW329 (1) R2 has only to be used for antenna cable lengths of more than 500 mm. Fig.1 Block diagram. 6 PINNING PIN TYPE(1) TXDEN 1 O control pin providing connection to an RS485 interface; note 2 RXLOW_DSP 2 I interface to the HITAG long range board RXHIGH_DSP 3 I SYMBOL FUNCTION RXCOL_DSP 4 I TXµPL_DSP 5 O SCLK_DSP 6 I SFFT_DSP 7 O i.c. 8 − internally connected; this pin must not be connected ACNMAN_DSP 9 O interface to the HITAG long range board HINMIRO_DSP 10 O RxD 11 I serial interface input from host; note 2 TxD 12 O serial interface output to host; note 2 i.c. 13 − internally connected; this pin must not be connected i.c. 14 − internally connected; this pin must not be connected OUT1 15 O OUT2 16 O output pins of the microcontroller for controlling e.g. a LED (connection of e.g. a BS170 or BSS123 as driver); note 2 IN1 17 I IN2 18 I input pins for optional switch; must be active LOW; maximum input voltage 5 V; internal pull-up resistors are provided; note 2 DVDD 19 P digital supply voltage (5 V) DGND 20 P digital ground supply n.c. 21 − not connected AVDD 22 P analog supply voltage (5 V) AGND 23 P analog ground supply 2001 Oct 04 4 Philips Semiconductors Product specification HITAG core module hardware HTCM400 PIN TYPE(1) NRESET 24 O output from the Power-on reset circuit; can be used as a reset signal (sink current is typical 10 mA and minimum 2 mA) n.c. 25 − not connected TX1 26 O antenna output RX 27 I antenna input SYMBOL FUNCTION Notes 1. O = output pin; I = input pin; P = power supply pin. 2. Input or output current on any pin is 1.5 mA; maximum capacitive load on any pin is 80 pF. handbook, halfpage 1 2 3 4 5 6 7 8 9 10 11 12 13 14 27 26 25 24 23 22 21 20 19 18 17 16 15 MGU473 Fig.2 Core module with its pin connectors and pin numbering (seen from below the module). 2001 Oct 04 5 Philips Semiconductors Product specification HITAG core module hardware 7 HTCM400 FUNCTIONAL DESCRIPTION 7.1 System overview The HITAG core module is a compact module used in read and write devices for the 125 kHz family. With only a few external components (antenna coupling network, interface driver and voltage decoupling) you can use the HTCM400 as the central part of a HITAG reader module (see Fig.3). handbook, full pagewidth I/O FUNCTIONS HOST SYSTEM POWER SUPPLY HTCM400 HITAG 1 ANTENNA MGW324 HITAG 2 Fig.3 System overview. 7.1.1 TRANSPONDERS The HTCM400 integrated into a read and write device can communicate with Philips HITAG 1 and HITAG 2 transponders. 7.1.2 VDD HOST SYSTEM C R2 RX L TxD RxD AGND MGW332 Fig.4 Connecting the antenna. I/O FUNCTIONS The I/O lines form the connection to potential keys and LEDs; two lines are wired as inputs and two as outputs. 7.1.4 TX1 CORE MODULE HTCM400 The connection to the host (e.g. microprocessor or PC) is a serial interface on CMOS level for data transmissions over shorter distances. You can connect an RS232 as well as an RS422 interface device. If you use an additional pin of the HTCM400 (pin TXDEN) as control pin, you can realize an RS485 interface. 7.1.3 antenna R1 (optional) handbook, halfpage The resistor R1 has to be used if the antenna voltage is too high (see Section 11.7). With the capacitor C the antenna tuning is done. R2 has only to be used for antenna cable lengths of more than 500 mm and is used for damping. CONNECTING THE ANTENNA Connect an antenna as shown in Fig.4 2001 Oct 04 For more details concerning the design of HITAG proximity antennas, see Section 11. 6 Philips Semiconductors Product specification HITAG core module hardware 7.1.5 HTCM400 7.3.3 BEHAVIOUR WITH SEVERAL TRANSPONDERS INTERFACE: MICROCONTROLLER - HOST If several HITAG transponders arrive simultaneously within the communication field of the antenna of a HITAG proximity reader module, the ‘stronger’ transponder (the nearer one) takes over or - under special circumstances no communication takes place. If the transponders arrive in the field one after the other, communication is established with the first one, all other transponders are ignored. The device communicates with the host (microcontroller or PC) via a serial interface using a baud rate of 9600 baud. Data transfer details are: 1 start bit, 8 data bits, 1 stop bit and no parity bit, the least significant bit is sent first. Nevertheless, it is possible to mute transponders so that several HITAG transponders can be accessed sequentially. This ensures that no two (or several) HITAG transponders will ever be processed (above all written to) accidentally at the same time. 7.3.4 An RS232 interface device can be connected to the HTCM400. Optionally an RS422 or an RS485 device is possible. The transmitter receives data from the microcontroller and modulates the carrier. The receiver demodulates the received data and passes them on to the microcontroller for further processing. If a HITAG long range reader module is used, anticollision mode is applied, which makes it possible to read and write all the HITAG 1 transponders (theoretical up to 232) within the communication field of the antenna simultaneously. Because of the mutual influence of the transponder coils they detune each other if there are too many too close to each other - the number of the transponders that can be operated simultaneously is limited. 7.2 TRANSMITTER AND RECEIVER 7.3.5 ANTENNA For the design of HITAG proximity antennas, see Section 11. 7.3.6 HITAG LONG RANGE READER MODULE The HITAG long range reader module (HTRM800) supplied by Philips uses some of the module pins as interface to an additional high frequency part and a Digital Signal Processor (DSP) part. Core module software The software description is given in document “HTCM400, HTRM440 Family, HTRM800 Family Interface Protocol Reader - Host”. 7.3.7 INTERFACE: MICROCONTROLLER - HITAG LONG RANGE BOARD 7.3 7.3.1 Core module hardware This interface is not wired with proximity applications (leave pins open). EEPROM The EEPROM is used to store non-volatile data such as personalization data, keys, passwords, configurations and status information. 7.3.2 MICROCONTROLLER The microcontroller processes the protocol for the communication between the transponders and the read and write unit. The interface signals are converted so that a HITAG 1 or HITAG 2 transponder is able to process them and the outgoing signals from the transponder are converted into interface-compatible signals. The second essential microcontroller function is its control function. The microcontroller activates and deactivates the transmitter and selects the EEPROM. 2001 Oct 04 7 Philips Semiconductors Product specification HITAG core module hardware 7.4 HTCM400 Postal approval Electromagnetic emission comply with the guidelines in FTZ 17 TR 2100 and ETS 300 683. Electromagnetic immunity complies with the guidelines in ETS 300 683. The postal approval can only be granted for final products, not just for components like the HTCM400. But the core module is designed in a way that it is possible to get the postal approval for a device including the HTCM400, if you follow the design instructions given by Philips. 7.4.1 COMMON MODE FILTERING Figure 5 shows the basic configuration using the HTCM400 used to comply with the standards and some additional circuits which are recommended. handbook, full pagewidth (1) 1 nF power supply 5 V DC 100 nF DVDD, AVDD (1) DGND, AGND 1 nF HTCM400 1 nF 1 nF TxD RxD GND RS232interface 1 nF ANTENNA TX1 RX AGND 1 nF 1 nF MGW326 (1) SMD filter Murata NFM61R10T102. Fig.5 Common mode filtering. The design consists of a virtual ground layer (drawn grey in Fig.5). All entering wires are blocked by 1 nF ceramic capacitors to this layer to prevent common mode disturbances from entering the following circuits. The 2001 Oct 04 virtual ground layer is floating, it is not connected to the ground itself. A recommended metal housing that covers the HTCM400 would also be connected to the floating layer. 8 Philips Semiconductors Product specification HITAG core module hardware 7.4.2 HTCM400 FILTERING OF THE SUPPLY VOLTAGES The transmitter of the HTCM400 is supplied via pins AVDD and AGND. Disturbances on these supply pins are amplified and may reduce the performance of the system. For that reason especially the analog supply voltage (pin AVDD) must be filtered in addition to the common mode filtering described in Fig.5. On the other hand the spurious emissions at the supply connections (pins DVDD and DGND) caused by the digital parts of the module must be limited. A suppressor diode protects the core module from ESD to the power supply line (see Fig.6). 100 µH handbook, full pagewidth DVDD 100 nF HTCM400 10 µH VP AVDD 100 nF GND 22 µF 100 nF 18 V suppressor AGND, DGND 10 µH MGW327 Fig.6 Power supply filtering. 7.4.3 FILTERING OF THE ANTENNA CIRCUIT In case of using an external antenna with shielded antenna cable, no additional filtering should be necessary. In case of a heavy disturbed environment, an additional filter circuit is recommended when using external antennas (see Fig.7). Using this filter will reduce the reading performance by approximately 20%. handbook, halfpage ANTENNA TX1 2.2 kΩ RX 1.68 nF 1 mH 10 kΩ HTCM400 GND MGW328 Fig.7 Filtering of the antenna circuit. 7.4.4 ESD PROTECTION All I/Os should be protected by common circuits consisting of series resistors and suppressor diodes. The transmitter output is already protected by a series resistor and internal diodes of the driving FETs. To protect the receiver’s input, a 40 V bi-directional suppresser diode at pin TX1 is recommended. If the additional filter shown in Fig.7 is used, no more protection circuits are needed. 2001 Oct 04 9 Philips Semiconductors Product specification HITAG core module hardware 7.5 HTCM400 7.6.3 Security considerations The use of cryptography (Stream Cypher), mutual authentication and password verification prevents monitoring and copying the data channel. Therefore, the area of the transponder that only can be accessed enciphered is called ‘secret area’. Developing the HTCM400 special consideration was given to aspects of security. The following items represent the fundamental framework of the security concept: • Cryptography • Mutual authentication To make use of cryptography you need secret data: keys and logdata. • Password verification and • Cyclic Redundancy Check (CRC). 7.6 Keys are used to initialize the crypto block and logdata are used for mutual authentication. Data reliability The transponders and the HITAG proximity reader module are provided with identical transport keys and transport logdata so that you can start operating them right away (see Table 1). All the commands and data transferred from the HTRM440 to the transponder are secured by Cyclic Redundancy Check (CRC). 7.6.1 DATA PRIVACY CRC OF A DATA STREAM BETWEEN READER Table 1 MODULE AND TRANSPONDER Transport values predefined by Philips. This check is carried out in the transponder. SYSTEM Every data stream sent (commands, addresses and user data) from the HTRM440 to the transponder is first checked for data errors by a transponder-integrated 8-bit CRC generator and then executed. Normally the transponder responds to each data stream from the HITAG proximity reader module with an acknowledge signal or with a data signal or with a data block. The CRC is formed over commands and addresses or the plain data respectively and in the case of encrypted mode it is also encrypted. The generator polynomial of the transponder CRC generator reads: HITAG 1 HITAG 2 VALUE keyinit password 0x00000000 keys 0x00000000 logdata 0x00000000 keyinit password 0x00000000 key 0x4D494B524F4E password TAG 0xAA4854 password RWD 0x4D494B52 In order to offer our OEM clients high flexibility, the configuration of the transponder, memory, password, keys and logdata can be changed. We strictly recommend to rigorously restrict these possibilities for the end customers (by setting the configuration page to read only, setting password, keys and logdata to neither read nor write). u8 + u4 + u3 + u2 + 1.............. = 0x1D and the CRC preassignment is: 0xFF. Detailed instructions how to use and calculate Cyclic Redundancy Check (CRC) are available in an additional document. 7.6.2 PARAMETER See also “HTCM400, HTRM440 Family, HTRM800 Family Interface Protocol Reader - Host”. CHECKING USER DATA 7.7 This check is carried out in the HITAG proximity reader module. The following mechanisms ensure the operation security of the HITAG system: Security of the data read from the transponder by the HITAG proximity reader module remains with the user for reasons of flexibility. Therefore, you can choose flexible check sums and store them in the EEPROM together with the data. You can protect sensitive data better than less sensitive data, thus permitting optimized operation times. 2001 Oct 04 Operating security • Anticollision mode • Monitoring the supply voltage • Antenna rupture or short-circuit. 10 Philips Semiconductors Product specification HITAG core module hardware 7.7.1 HTCM400 ANTICOLLISION MODE over. By muting a selected transponder (HALT mode) another transponder that is to be found in the communication field of the antenna can be recognized. Anticollision mode in long range applications permits you to process several HITAG 1 transponders simultaneously. Theoretically up to 232 transponders can be processed simultaneously. In practice this number is limited because of the mutual influence of the transponders - they detune each other, if there are too many too close to each other. 7.7.2 Supply voltage is controlled by a Watchdog circuit which triggers a system reset if the supply voltage drops below 4.75 V or if the microcontroller fails. In proximity applications using HITAG 1 or HITAG 2 transponders, only one transponder is handled even if there are several transponders within the communication field of the antenna. In this case either no communication takes place or the ‘stronger’ or closer transponder takes 8 MONITORING THE SUPPLY VOLTAGE 7.7.3 ANTENNA RUPTURE OR SHORT-CIRCUIT The HTCM400 does not get permanently damaged in case of an antenna rupture or a brief antenna short-circuit. ELECTRICAL SPECIFICATIONS SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT Power supply VP DC supply voltage 4.75 5.0 5.25 V IP DC supply current − − 100 mA P power dissipation − 0.5 − W Vripple(p-p) ripple voltage (peak-to-peak value) fripple is <10 kHz; note 1 − − 5 mV fripple is 10 to 20 kHz; note 1 − − 25 mV fripple is ≥20 kHz; note 1 − − 40 mV Modulation mTX modulation ratio of reader module Amplitude Shift Keying (ASK) to transponder − 100(2) − % mRX modulation ratio of transponder to Amplitude Shift Keying (ASK); reader module note 3 − − − % Temperature Toper operating temperature −25 − +85 °C Tstg storage temperature −40 − +85 °C Notes 1. With the power supply filter described in Section 7.4.2. 2. The carrier is periodically blanked completely, the information is located in the intervals between the pauses. 3. Modulation ratio depending on the distance between transponder and reader module. 2001 Oct 04 11 Philips Semiconductors Product specification HITAG core module hardware 9 HTCM400 MECHANICAL SPECIFICATIONS 9.2 The outer dimensions of the PCB are: 86 × 40 × 7 mm. The module consists of the Printed-Circuit Board (PCB) and one 14-pole and one 13-pole pin connector that protrudes from the PCB. 9.1 Dimensions The module including the pin connectors is approximately 18 mm high. Mounting the module You can mount the module onto a base printed-circuit board by soldering or plugging. handbook, full pagewidth 26.7 7.3 0.64 2.54 25.4 1 2 3 4 5 6 7 8 9 10 11 12 13 14 27 26 25 24 23 22 21 20 19 18 17 16 15 60.0 86.0 18 40 MGW325 26.3 13.0 32.0 4.0 40.0 Dimensions are in mm. Fig.8 Dimensions (seen from below the module) and pins protruding. 2001 Oct 04 12 Philips Semiconductors Product specification HITAG core module hardware HTCM400 10 APPLICATION INFORMATION 10.2 10.1 In order to be able to operate two systems side by side without negative influence on communication ranges, you must place the antennas at a minimum distance of four times the antenna diameter. If you place them at a closer distance be sure to use suitable shielding or synchronization. Metallic environment, interferences The communication range is impaired by metallic environment and electromagnetic interferences (e.g. monitors and keyboards). Therefore, you should keep a distance of at least the antenna’s diameter to metallic surfaces or loops as well as to electromagnetic interferences. If this is not possible, you have to take preventive measures such as using ferrites for transponders and antennas or shielding for antennas. 10.3 Distance between two antennas To build a proximity reader handbook, full pagewidth other 125 kHz transponders CORE MODULE HTCM400 serial interface HITAG antenna tags MGW330 Fig.9 Block diagram of proximity reader module. 10.3.1 CONNECTION OF THE HTCM400 IN ORDER TO BUILD A PROXIMITY READ AND WRITE DEVICE. A few external components are needed to make the HTCM400 a proximity read and write device (see Fig.10). handbook, full pagewidth POWER SUPPLY filter on/off switch (optional) DVDD OUT1 AVDD OUT2 DGND IN1 AGND IN2 I/O FUNCTIONS (if needed) CORE MODULE HTCM400 SERIAL INTERFACE DRIVER (if needed) RxD TX1 TxD RX TXDEN AGND ANTENNA COUPLING MGW333 Fig.10 Building a proximity read/write device. 2001 Oct 04 13 Philips Semiconductors Product specification HITAG core module hardware 10.3.2 HTCM400 POWER SUPPLY distances the transmission can be done over an RS232 interface, longer distances require integration of an RS485 or RS422 interface component. If you use an RS485 interface, pin TXDEN is used as control pin. The HTCM400 requires a DC voltage of 5 V ± 5% and it is absolutely necessary to use a low resistance (<0.7 Ω) power supply. Voltage regulation is required and separate supplies for analog and digital parts are recommended. See Section 8 for maximum allowed power supply ripple amplitudes. 10.3.3 10.3.4 I/O FUNCTIONS If necessary, you can connect these inputs and outputs to drivers for LEDs and switches. INTERFACE DRIVER Signal transmission for direct connection to the host can be done over the serial CMOS interface. For short 10.4 To build a long range reader handbook, full pagewidth other 125 kHz transponders RF PART CORE MODULE HTCM400 serial interface DSP HITAG tags antenna MGW331 Fig.11 Block diagram of long range reader module. 10.5 • Interference received by the antenna because of an external noise source (e.g. monitor or keys). Remedial measure: removal of the antenna from the interfering area Possible sources of errors by connecting the HTCM400 The following error list should be checked if any error (e.g. read and write distances that do not reach the specified values) occurs: • Connecting cables of the antenna changed by mistake • Antenna is mounted in metal environment. Remedial measure: mount a non-metal space keeper between the antenna and the metal • Power supply cable not mounted correctly • Bad filtering of the power supply; remedial measure: filtering as described in Section 7.4.2 • Antenna is not designed following the design instructions of Section 11 • DC power supply not within the specified range (VP = 5 V ± 5%) • Inductance of the antenna is too high • RS232 interface not connected correctly • Quality factor of the antenna is too high (Q > 40) • Interference received by the HTCM400 because of the digital part of a possible additional circuit board. Remedial measure: shielding of the additional circuit board • Antenna current is too high • Antenna voltage is too high. • Interference received by the HTCM400 because of an external noise source. Remedial measure: housing of metal or shielding 2001 Oct 04 14 Philips Semiconductors Product specification HITAG core module hardware HTCM400 11 INSTRUCTIONS FOR BUILDING HITAG PROXIMITY ANTENNAS within the limit values 3 and 1. If the ratio is too big or too small read/write distances can decrease and difficulties during data transmission may occur. For applications in which the transponders are only to be read, you can also use antennas that do not meet these instructions. The antenna is an important part in the data transmission process between read and write device and transponder. Therefore, you should be particularly careful when implementing the antenna in order to achieve optimum results. 11.1 Basics Figure 12 shows the general architecture of a HITAG proximity antenna and its connection to the HTCM400. An essential aspect in dimensioning HITAG proximity antennas is the ratio between the antenna diameter and the diameter of the transponder coil. This ratio should be handbook, full pagewidth R1 TX1 Cs Ia Vo Cs RX R2 L VL CORE MODULE Ls R2 Rs AGND ANTENNA MGW273 antenna equivalent circuit Fig.12 Architecture of a proximity antenna. The resistor R1 (22 Ω) in Fig.12 is used as current limiter. It protects the output stage in the event of a possible short circuit in the antenna and is already integrated in the HTCM400. R2 (approximately 600 to 1000 Ω) has only to be used for antenna cable lengths of more than 50 cm. When developing an antenna, it is important to take into consideration the read/write device limits, i.e. maximum antenna current and maximum voltage at the receiver input. With an output voltage Vo of approximately 2.5 V (p-p) the following limits apply to the HTCM400: • Maximum antenna current is 100 mA (p-p) • Maximum input voltage at the receiver (VL) is 32 V (p-p). 2001 Oct 04 15 Philips Semiconductors Product specification HITAG core module hardware 11.2 HTCM400 Antenna coil 11.3 The inductance of the coil should be between 350 and 500 µH. Measuring the inductance The inductance of the coil designed according to the instructions as given in Section 11.2 can be measured using the measuring set-up as shown in Fig.13. The antenna quality factor (Q) should be approximately 40. 2×π×f×L Q = -----------------------------Rs handbook, halfpage If the Q factor is too high, it must be reduced with an additional resistor. It is better not to use this additional resistor, but instead to use a smaller wire diameter of the coil. Ia R 47 Ω f = 125 kHz L The following formula describes the approximate calculation of the number of windings for a desired inductance and antenna geometry: VL MGW275 1.9 a L = 2 × a × ln ---- – K × N D Fig.13 Measuring the inductance of the coil. where: L is desired inductance in nH A sinus signal of 125 kHz is fed using a function generator. If you measure the current Ia and the antenna voltage VL you can calculate the inductance according to the formula: VL L = -------------where ω = 2 × π × f . ω × Ia a is antenna circumference in cm D is wire diameter in cm N is number of windings K is a geometrical constant: For a circular antenna K = 1.01 11.4 For a square antenna K = 1.47. For optimal performance, the antenna cable length should not exceed 5 m. a Remark: the factor K is normally much smaller than ---- and D can therefore be left out: N ≈ 1.9 2001 Oct 04 Antenna cable length L ---------------------------------a 2 × a × ln ---- D 16 Philips Semiconductors Product specification HITAG core module hardware 11.5 HTCM400 Antenna tuning You have to tune the antenna in its final form with the connecting cable. You must not make any changes to the antenna coil or the connecting cable after you finished tuning because mechanical changes influence the electrical values and the antenna is detuned again. R1 handbook, full pagewidth 47 Ω Cs Va R2 Vo f = 125 kHz L MGW274 R3 1Ω VR Fig.14 Tuning the antenna. A sinus signal of 125 kHz is fed to the antenna using a frequency generator. You measure the voltages Va and VR with an oscilloscope. Then you change the frequency until Va and VR are in phase. If the resonance frequency now is too high, you have to increase CS. If it is too low, you have to decrease CS. 11.6 Determining the serial resistance of the antenna Use an oscilloscope to measure Va and VR at a frequency of 125 kHz. You can calculate the serial resistance RS of V the antenna with the following formulas: I a = ------R- and R3 The aim is to get a resonance frequency of 125 kHz using CS. V R s = -----aIa The resonant frequency has to be in the range of 125 ± 4 kHz. 11.7 Checking the antenna voltage VL Before connecting the antenna to the read and write device in Fig.15, you must carry out a check calculation of the input level of the read and write device according to the next formulas in order to prevent damage. handbook, full pagewidth R1 Re TX1 Ia Vo Cs RX R2 L VL CORE MODULE AGND MGW276 Fig.15 Calculation check of the input level. 2001 Oct 04 17 Philips Semiconductors Product specification HITAG core module hardware HTCM400 of the metal shorter than the maximum antenna diameter) Vo I a = ---------------------------------R1 + R s + R e • Measurement of the inductance L of the antenna is described in Section 11.3 Vo ≈ 2.5 V • Determination of the serial capacitor CS is described in Section 11.5 VL = L × ω × Ia where ω = 2 × π × f (f = 125 kHz) The maximum value for VL reads 32 V (p-p), safeguarding against damage to the input level of the read/write device: Remark: the capacitance of the antenna supply cable can be measured or found out in the data sheet of the cable (e.g. Cp = 180 pF/m) • With VL < 32 V (p-p) the resistance Re can be omitted • With VL > 32 V (p-p) you have to calculate and insert Re according to the following formula: Vo R e = L × ω × ----------------- – R1 – R s and V L(max) • Now the antenna has to be tuned according to Section 11.5. The tuning is acceptable if the resonant frequency is within a range of 125 ± 4 kHz • The serial resistance Rs of the antenna is the impedance of the tuned antenna and is an ohmic resistance at the resonance frequency (f = 125 kHz). It can be calculated as shown in Section 11.6 Re ≥ L × ω × 0.078 − 22 − Rs 11.8 Procedure for practical antenna design • To get a satisfactory reading distance the quality factor of the antenna coil (for non-metal environment) should be approximately Q = 40. The quality factor of a coil is 2×π×f×L ω×L calculated as follows: Q = ------------- = -----------------------------Rs Rs The procedure how to design a HITAG proximity antenna is described in the previous sections. The main steps are the following: • The desired inductance for the antenna coil can be chosen in a range between 350 and 500 µH; e.g. L = 420 µH • By knowing RS and the dropping resistor (R1 = 22 kΩ) it is possible to calculate the current Ia and the antenna voltage VL. • The number of windings N can be calculated with the following formula: N = 1.9 L ( nH ) -------------------------------------------------a 2 × a × ln × ---- – K D It is very important to calculate the antenna voltage before connecting the antenna to the HTCM400 to avoid damage. Is the calculated value of VL higher than 32 V (p-p) a resistor Re has to be integrated to protect the module output circuit. The resistor has to be placed as shown in Section 11.7 For L = 420 µH: N= 1.9 420000 633 -------------------------------------------- = --------------------------------a a 2 × a × ln ---- – K 1.9 a × ln --- D D • After checking the antenna voltage connect your antenna to the HTCM400 and measure the read/write distances with your transponders. If the read/write distances do not fulfil your expectations, the following points should be considered: Remark: the factor K (see Section 11.2) normally is a much smaller than ---- and therefore can be left out. D – The size of the antenna and the size of the transponder have to be in a defined ratio (between 3 and 1). That means, if you increase the antenna over a certain size, the maximum read/write distances will decrease by the use of the same transponder • Now the antenna can be built up with the desired dimensions (circumference a) with the calculated number of turns. Remark: the antenna coil must be changed afterwards because with the mechanical dimensions the electrical specifications are changing too. That means the number of turns, the shape, arrangement of the coil windings and antenna supply cable must be in their final form. – The optimal shape of the antenna coil is a circle. The performance of a square shaped coil is much better than that of a rectangular shaped coil (with the same circumference) Remark: metal influences the electrical characteristics of the antenna very much. That is why all future tasks have to be done with the antenna in its final environment if metal will be in the antenna’s neighbourhood (distance 2001 Oct 04 – To get better read/write distances the quality factor of the antenna coil should be increased, but it must not be higher than Q = 40. This can be reached by the following measures: 18 Philips Semiconductors Product specification HITAG core module hardware HTCM400 In this case cards and coins can be used and the following approximate communication distances should be achieved: – All conducting material has to be removed from the antenna environment – A thicker wire can be used for the coil Read distances with HITAG 1 and 2 card: 120 mm – Ferrite can be placed behind the antenna coil to concentrate the field Read distances with HITAG 1 and 2 coin: 65 mm. – Extension of the antenna area The third antenna configuration is the smallest one: – There can be better results by trying another number of turns. Ø 0.224 mm Cu; lacquer wire; 85 turns Diameter of the turns (internal) is 35 mm Attention: all these measures must not differ from the antenna design instructions of Section 11. Tuning frequency is 125 kHz Tuning capacity depending on the length of the antenna cable and the exact way of winding. Remark: with additional dropping resistors R1 and Re the quality factor of the whole antenna system is approximately 15. 11.9 Using this antenna coins and pills can be operated up to the following approximate distances: Read distance with HITAG 1 coin: 58 mm Reference antennas Read distance with HITAG 1 pill: 28 mm. Designing an antenna in the way described in Chapter 11 you could use the following values: All distances are given in free air at room temperature. Ø 0.4 mm Cu; lacquer wire; 35 turns Diameter of the turns (internal) is 145 mm 12 SURVEY OF REFERENCED DOCUMENTS Tuning frequency is 125 kHz CATEGORY Tuning capacity depending on the length of the antenna cable and the exact way of winding. Data sheet This antenna is best suitable for HITAG 1 and 2 cards. In this performance reading distances of approximately 150 mm should be achieved. A further antenna configuration: Ø 0.224 mm Cu; lacquer wire; 52 turns Diameter of the turns (internal) is 65 mm Tuning frequency is 125 kHz Tuning capacity depending on the length of the antenna cable and the exact way of winding. 2001 Oct 04 19 TITLE “HTCM400, HTRM440 Family, HTRM800 Family HITAG Interface Protocol Reader - Host” Philips Semiconductors Product specification HITAG core module hardware HTCM400 13 DATA SHEET STATUS DATA SHEET STATUS(1) PRODUCT STATUS(2) DEFINITIONS Objective data Development This data sheet contains data from the objective specification for product development. Philips Semiconductors reserves the right to change the specification in any manner without notice. Preliminary data Qualification This data sheet contains data from the preliminary specification. Supplementary data will be published at a later date. Philips Semiconductors reserves the right to change the specification without notice, in order to improve the design and supply the best possible product. Product data Production This data sheet contains data from the product specification. Philips Semiconductors reserves the right to make changes at any time in order to improve the design, manufacturing and supply. Changes will be communicated according to the Customer Product/Process Change Notification (CPCN) procedure SNW-SQ-650A. Notes 1. Please consult the most recently issued data sheet before initiating or completing a design. 2. The product status of the device(s) described in this data sheet may have changed since this data sheet was published. The latest information is available on the Internet at URL http://www.semiconductors.philips.com. 14 DEFINITIONS 15 DISCLAIMERS Short-form specification The data in a short-form specification is extracted from a full data sheet with the same type number and title. For detailed information see the relevant data sheet or data handbook. Life support applications These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be expected to result in personal injury. Philips Semiconductors customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Philips Semiconductors for any damages resulting from such application. Limiting values definition Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 60134). Stress above one or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended periods may affect device reliability. Right to make changes Philips Semiconductors reserves the right to make changes, without notice, in the products, including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no licence or title under any patent, copyright, or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask work right infringement, unless otherwise specified. Application information Applications that are described herein for any of these products are for illustrative purposes only. Philips Semiconductors make no representation or warranty that such applications will be suitable for the specified use without further testing or modification. 2001 Oct 04 20 Philips Semiconductors Product specification HITAG core module hardware HTCM400 NOTES 2001 Oct 04 21 Philips Semiconductors Product specification HITAG core module hardware HTCM400 NOTES 2001 Oct 04 22 Philips Semiconductors Product specification HITAG core module hardware HTCM400 NOTES 2001 Oct 04 23 Philips Semiconductors – a worldwide company Contact information For additional information please visit http://www.semiconductors.philips.com. Fax: +31 40 27 24825 For sales offices addresses send e-mail to: [email protected]. SCA73 © Koninklijke Philips Electronics N.V. 2001 All rights are reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license under patent- or other industrial or intellectual property rights. Printed in The Netherlands 613502/02/pp24 Date of release: 2001 Oct 04 Document order number: 9397 750 08333