s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e XT55 Siemens Cellular Engine Version: DocID: 00.02 XT55_hd_v00.02 XT55_hd_v00.02 Page 1 of 116 17.03.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Document Name: XT55 Hardware Interface Description Version: 00.02 Date: March 17, 2004 DocId: XT55_hd_v00.02 Status: Confidential / Preliminary General note Product is deemed accepted by Recipient and is provided without interface to Recipient´s products. The Product constitutes pre-release version and code and may be changed substantially before commercial release.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Contents 0 Document history....................................................................................................... 8 1 Introduction ................................................................................................................ 9 1.1 Related documents ............................................................................................. 9 1.2 Terms and abbreviations......................
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e 3.6.5 Timing of the GSM_CTS signal in CYCLIC SLEEP modes...................48 3.6.6 Wake up XT55 from SLEEP mode .......................................................50 3.7 Summary of state transitions (except SLEEP mode)..........................................52 3.8 RTC backup for GSM/GPRS part of XT55 .........................................................53 3.9 Serial interfaces of the XT55 GSM/GPRS part.................
s XT55 Hardware Interface Description Confidential / Preliminary 6.6 6.7 6.8 6.9 mo b i l e Electrical characteristics of the voiceband part...................................................99 6.6.1 Setting audio parameters by AT commands .........................................99 6.6.2 Audio programming model .................................................................100 6.6.3 Characteristics of audio modes ..........................................................101 6.6.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Figures Figure 1: Block diagram of serial interface concept ..............................................................23 Figure 2: Block diagram of XT55 for SiRF Demo application................................................24 Figure 3: Block diagram of XT55 with AVL or TCP/IP application (optional).........................24 Figure 4: Power supply limits during transmit burst ...............................................
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Figure 52: XT55 bottom view..............................................................................................107 Figure 53: Mechanical dimensions of XT55........................................................................108 Figure 54: Mounting holes on XT55 ...................................................................................109 Figure 55: Recommended dowel...........................................
s XT55 Hardware Interface Description Confidential / Preliminary 0 mo b i l e Document history Preceding document: "XT55 Hardware Interface Description" Version 00.01 New document: "XT55 Hardware Interface Description" Version 00.02 Chapter Page What is new Throughout this document · Maximum temperature has been changed from +65°C to +70°C. 1.1 9 Updated list of related documents 1.2 10 Added GPS terms abbreviations 2.1 19 Added new key features regarding GPS 2.
s XT55 Hardware Interface Description Confidential / Preliminary 1 mo b i l e Introduction This document describes the hardware interface of the Siemens XT55 module that connects to the cellular device application and the air interface. As XT55 is intended to integrate with a wide range of application platforms, all functional components are described in great detail. This guide therefore covers all information needed to design and set up cellular applications incorporating the XT55 module.
XT55 Hardware Interface Description Confidential / Preliminary 1.2 s mo b i l e Terms and abbreviations Abbreviation Description AD Analog / Digital ADC Analog-to-Digital Converter AFC Automatic Frequency Control AGC Automatic Gain Control ANSI American National Standards Institute ARFCN Absolute Radio Frequency Channel Number ARP Antenna Reference Point ASC0 / ASC1 Asynchronous Controller.
XT55 Hardware Interface Description Confidential / Preliminary Abbreviation Description DTX Discontinuous Transmission EFR Enhanced Full Rate EGSM Enhanced GSM EMC Electromagnetic Compatibility ESD Electrostatic Discharge ETS European Telecommunication Standard FCC Federal Communications Commission (U.S.
XT55 Hardware Interface Description Confidential / Preliminary s Abbreviation Description PAP Password Authentication Protocol PBCCH Packet Switched Broadcast Control Channel PCB Printed Circuit Board PCL Power Control Level PCM Pulse Code Modulation PCN Personal Communications Network, also referred to as DCS 1800 PCS Personal Communication System, also referred to as GSM 1900 PDU Protocol Data Unit PLL Phase Locked Loop PPP Point-to-point protocol PRN Pseudo-Random Noise Number –
XT55 Hardware Interface Description Confidential / Preliminary Abbreviation s mo b i l e Description Phonebook abbreviations FD SIM fixdialing phonebook LD SIM last dialing phonebook (list of numbers most recently dialed) MC Mobile Equipment list of unanswered MT calls (missed calls) ME Mobile Equipment phonebook ON Own numbers (MSISDNs) stored on SIM or ME RC Mobile Equipment list of received calls SM SIM phonebook XT55_hd_v00.02 Page 13 of 116 17.03.
XT55 Hardware Interface Description Confidential / Preliminary 1.3 s mo b i l e Type approval XT55 is designed to comply with the directives and standards listed below. Please note that the product is still in a pre-release state and, therefore, type approval and testing procedures have not yet been completed.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e Requirements of quality IEC 60068 DIN EN 60529 Environmental testing IP codes Compliance with international rules and regulations Manufacturers of mobile or fixed devices incorporating XT55 modules are advised to have their completed product tested and approved for compliance with all applicable national and international regulations.
XT55 Hardware Interface Description Confidential / Preliminary 1.4 s mo b i l e Safety precautions The following safety precautions must be observed during all phases of the operation, usage, service or repair of any cellular terminal or mobile incorporating XT55. Manufacturers of the cellular terminal are advised to convey the following safety information to users and operating personnel and to incorporate these guidelines into all manuals supplied with the product.
XT55 Hardware Interface Description Confidential / Preliminary SOS s mo b i l e IMPORTANT! Cellular terminals or mobiles operate using radio signals and cellular networks. Because of this connection cannot be guaranteed at all times under all conditions. Therefore, you should never rely solely upon any wireless device for essential communications, for example emergency calls.
XT55 Hardware Interface Description Confidential / Preliminary 2 s mo b i l e Product concept Designed for use on any GSM network in the world, Siemens XT55 is a tri-band GSM/GPRS engine that works on the three frequencies GSM 900 MHz, GSM 1800 MHz and GSM 1900 MHz and supports also GPS technology for satellite navigation. XT55 features GPRS multislot class 10 and supports the GPRS coding schemes CS-1, CS-2, CS-3 and CS-4.
s XT55 Hardware Interface Description Confidential / Preliminary 2.1 mo b i l e XT55 key features at a glance Table 1: XT55 key features Feature Implementation Power supply Supply voltage 3.3V – 4.8V for the GSM / GPRS module Separate power supply source: 3.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Feature Implementation FAX Group 3: Class 1, Class 2 SIM interface Supported SIM card: 3V External SIM card reader has to be connected via interface connector (note that card reader is not part of XT55) External antenna GSM / GPRS: GPS: Connected via 50 Ohm antenna connector or antenna pad. Separate GPS antenna connector. See Figure 51 for details.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Table 2: GSM/GPRS coding schemes and maximum net data rates over air interface Coding scheme 1 Timeslot 2 Timeslots 4 Timeslots CS-1: 9.05 kbps 18.1 kbps 36.2 kbps CS-2: 13.4 kbps 26.8 kbps 53.6 kbps CS-3: 15.6 kbps 31.2 kbps 62.4 kbps CS-4: 21.4 kbps 42.8 kbps 85.
XT55 Hardware Interface Description Confidential / Preliminary 2.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Active GPS antenna GSM antenna XT 55 GSM – GSM module GPS – Modul GPS module Modul GSM_RXD0 ASC0 GSM_TXD0 6 Modem Status lines ASC1 Serial data 2 Serial data 1 GSM_RXD1 GSM_TXD1 GSM_RTS1 GSM_CTS1 SDO2 SDI2 SDI1 SDO1 80 pin B2B 80 pin B2B Customer application Serial 1 GSM Serial 0 GSM Serial 2 Serial 1 GPS GPS Figure 1: Block diagram of serial interface concept XT55_hd_v00.02 Page 23 of 116 17.03.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e Figure 2: Block diagram of XT55 for SiRF Demo application Figure 3: Block diagram of XT55 with AVL or TCP/IP application (optional) XT55_hd_v00.02 Page 24 of 116 17.03.
s XT55 Hardware Interface Description Confidential / Preliminary 3 mo b i l e GSM/GPRS application interface The GSM/GPRS part of the XT55 module incorporates several sub-interfaces described in the following chapters: · Power supply and charging control (see Chapters 3.2 and 3.3) · Dual serial GSM interface (see Chapter 3.9) · Two analog audio interfaces and a digital audio interface (see Chapter 3.10) · SIM interface (see Chapter 3.
XT55 Hardware Interface Description Confidential / Preliminary Mode Function POWER DOWN Normal shutdown after sending the AT^SMSO command. s mo b i l e The Power Supply ASIC (PSU-ASIC) disconnects the supply voltage from the baseband part of the circuit. Only a voltage regulator in the PSU-ASIC is active for powering the RTC. Software is not active. The serial interfaces are not accessible. Operating voltage (connected to GSM_BATT+) remains applied.
s XT55 Hardware Interface Description Confidential / Preliminary 3.2 mo b i l e Power supply The power supply for the GSM/GPRS part of the XT55 module has to be a single voltage source of VGSM_BATT+= 3.3V...4.8V. It must be able to provide sufficient current in a transmit burst which typically rises to 1.6A. All the key functions for supplying power to the device are handled by an ASIC power supply.
s XT55 Hardware Interface Description Confidential / Preliminary 3.2.2 mo b i l e Minimizing power losses When designing the power supply for your application please pay specific attention to power losses. Ensure that the input voltage VGSM_BATT+ never drops below 3.3V on the GSM/GPRS part of the XT55 board, not even in a transmit burst where current consumption can rise to typical peaks of 1.6A. It should be noted that the GSM/GPRS part of the XT55 module switches off when exceeding these limits.
XT55 Hardware Interface Description Confidential / Preliminary 3.3 s mo b i l e Power up / down scenarios In general, be sure not to turn on GSM/GPRS part of the XT55 module while it is out of the operating range of voltage and temperature stated in Chapters 6.2 and 6.3. The GSM/GPRS part of the XT55 would immediately switch off after having started and detected these inappropriate conditions. 3.3.
s XT55 Hardware Interface Description Confidential / Preliminary 3.3.1.1 mo b i l e Turn on the GSM/GPRS part of XT55 using the ignition line GSM_IGT (Power on) To switch on the XT55 GSM/GPRS part the GSM_IGT (Ignition) signal needs to be driven to ground level for at least 100ms and not earlier than 10ms after the last falling edge of GSM_VDD. This can be accomplished using an open drain/collector driver in order to avoid current flowing into this pin. GSM_BATT+ min. 10ms HiZ min.
s XT55 Hardware Interface Description Confidential / Preliminary 3.3.1.2 mo b i l e Timing of the ignition process When designing your application platform take into account that powering up the GSM/GPRS part of the XT55 module requires the following steps. · The ignition line cannot be operated until VGSM_BATT+ passes the level of 3.0V. · The ignition line shall not be operated earlier than 10ms after the last falling edge of GSM_VDD. · 10ms after VGSM_BATT+ has reached 3.
XT55 Hardware Interface Description Confidential / Preliminary 3.3.1.3 s mo b i l e Turn on the GSM/GPRS part of XT55 using the GSM_POWER signal As detailed in Chapter 3.5.4, the charging adapter can be connected regardless of the module’s operating mode (except for Alarm mode). If the charger is connected to the charger input of the external charging circuit and the module’s GSM_POWER pin while XT55 is off, processor controlled fast charging starts (see Chapter 3.5.3).
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e If the charger is connected to the GSM_POWER line when GSM/GPRS part of the XT55 is in ALARM mode charging will start, while XT55 stays in ALARM mode. See also Chapter 3.7 which summarizes the various options of changing the mode of operation. If your host application uses the GSM_SYNC pin to control a status LED as described in Chapter 3.12.2.2, please note that the LED is off while the GSM engine is in Alarm mode. XT55_hd_v00.
XT55 Hardware Interface Description Confidential / Preliminary 3.3.2 s mo b i l e Turn off the GSM/GPRS part of XT55 To switch the module off the following procedures may be used: · · · Normal shutdown procedure: Software controlled by sending the AT^SMSO command over the serial application interface. See Chapter 3.3.2.1.
XT55 Hardware Interface Description Confidential / Preliminary 3.3.2.2 s mo b i l e Maximum number of turn-on / turn-off cycles Each time the module is shut down, data will be written from volatile memory to flash memory. The guaranteed maximum number of write cycles is limited to 100.000. 3.3.2.3 Caution: Emergency shutdown using GSM_EMERGOFF pin Use the GSM_EMERGOFF pin only when, due to serious problems, the software is not responding for more than 5 seconds.
XT55 Hardware Interface Description Confidential / Preliminary 3.3.3 s mo b i l e Automatic shutdown Automatic shutdown takes effect if · the XT55 board is exceeding the critical limits of overtemperature or undertemperature · the battery is exceeding the critical limits of overtemperature or undertemperature · undervoltage is detected The automatic shutdown procedure is equivalent to the power-down initiated with the AT^SMSO command, i.e.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e Table 6: Temperature dependent behavior Sending temperature alert (15 s after start-up, otherwise only if URC presentation enabled) ^SCTM_A: 1 Caution: Tamb of battery close to over temperature limit. ^SCTM_B: 1 Caution: Tamb of board close to over temperature limit. ^SCTM_A: -1 Caution: Tamb of battery close to under temperature limit. ^SCTM_B: -1 Caution: Tamb of board close to under temperature limit.
XT55 Hardware Interface Description Confidential / Preliminary 3.3.3.4 s mo b i l e Undervoltage shutdown if no battery NTC is present The undervoltage protection is also effective in applications, where no NTC connects to the GSM_BATT_TEMP terminal. Thus, you can take advantage of this feature even though the application handles the charging process or XT55 is fed by a fixed supply voltage.
XT55 Hardware Interface Description Confidential / Preliminary 3.4 s mo b i l e Automatic GPRS Multislot Class change Temperature control is also effective for operation in GPRS Multislot Class 10. If the board temperature increases to the limit specified for restricted operation1) while data are transmitted over GPRS, the module automatically reverts from GPRS Multislot Class 10 (2 Tx) to Class 8 (1Tx). This reduces the power consumption and, consequently, causes the board’s temperature to decrease.
s XT55 Hardware Interface Description Confidential / Preliminary 3.5 mo b i l e GSM charging control The GSM/GPRS part of the XT55 module integrates a charging management for Li-Ion batteries. You can skip this chapter if charging is not your concern, or if you are not using the implemented charging algorithm. XT55 has no on-board charging circuit. To benefit from the implemented charging management you are required to install a charging circuit within your application.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Table 7: Bill of material for external charging circuit Part Description SI3441DV p-chan 2.5V (G-S) MOSFET VISHAY: SI3441DV-T1 (TSOP-6) NEC: 1SS355 100mA Si-diode (UMD2) ROHM: Toshiba: 1SS352TPH3 CRS04 1A Schottky diode Toshiba: CRS04 4V3 250mW; 200mA; 4.3V Z-Diode (SOD323) Philips: ESDA6V1-5W6 ESD protection TRANSIL™ STM: array 470R, 3k3, 10k Resistor, e.g.
s XT55 Hardware Interface Description Confidential / Preliminary 3.5.1 mo b i l e Battery pack characteristics The charging algorithm has been optimized for a Li-Ion battery pack that meets the characteristics listed below. It is recommended that the battery pack you want to integrate into your XT55 application is compliant with these specifications.
XT55 Hardware Interface Description Confidential / Preliminary 3.5.2 s mo b i l e Recommended battery pack specification Table 8: Specifications of recommended battery pack Nominal voltage 3.6V Capacity 800mAh NTC 10kΩ ± 5% @ 25°C, B (25/85)=3435K ± 3% Overcharge detection voltage 4.325 ± 0.025V Overcharge release voltage 4.075 ± 0.025V Overdischarge detection voltage 2.5 ± 0.05V Overdischarge release voltage 2.9 ± 0.5V Overcurrent detection 3 ± 0.
s XT55 Hardware Interface Description Confidential / Preliminary 3.5.3 mo b i l e Implemented charging technique If the external charging circuit follows the recommendation of Figure 9, the charging process consists of trickle charging and processor controlled fast charging. For this solution, the fast charging current provided by the charger or any other external source must be limited to 500mA.
s XT55 Hardware Interface Description Confidential / Preliminary Note: mo b i l e Do not connect the charger to the GSM_BATT+ lines. Only the charger input of the external charging circuit is intended as input for charging current! The GSM_POWER pin of XT55 is the input only for indicating a connected charger! The battery manufacturer must guarantee that the battery complies with the described charging technique.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e Features of Charge-only mode Once the GSM engine enters the Charge-only mode, the AT command interface presents an Unsolicited Result Code (URC) which reads: ^SYSSTART CHARGE-ONLY MODE Note that this URC will not appear when autobauding was activated (due to the missing synchronization between DTE and DCE upon start-up). Therefore, it is recommended to select a fixed baudrate before using the Charge-only mode.
XT55 Hardware Interface Description Confidential / Preliminary 3.6 s mo b i l e Power saving SLEEP mode reduces the functionality of the GSM/GPRS part of the XT55 module to a minimum and, thus, minimizes the current consumption to the lowest level. Settings can be made using the AT+CFUN command. For details see below and [1]. SLEEP mode falls into two categories: · NON-CYCLIC SLEEP mode AT+CFUN=0 · CYCLIC SLEEP modes, selectable with AT+CFUN=5, 6, 7, 8 or 9.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e The CYCLIC SLEEP modes give you greater flexibility regarding the wake-up procedures: For example, in all CYCLIC SLEEP modes, you can enter AT+CFUN=1 to permanently wake up the module. In modes CFUN=7 and 8, the GSM/GPRS part of the XT55 automatically resumes power saving, after you have sent or received a short message or made a call.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e GSM_CTS will also be activated if any character is to be sent. After the last character was sent or received the interface will remain active for · another 2 seconds, if AT+CFUN=5 or 7, · another 10 minutes, if AT+CFUN=6 or 8, · or for an individual time defined with AT^SCFG, if AT+CFUN=9. Assertion of GSM_RTS has the same effect.
s XT55 Hardware Interface Description Confidential / Preliminary 3.6.6 mo b i l e Wake up XT55 from SLEEP mode A wake-up event is any event that causes the module to draw current. Depending on the selected mode the wake-up event either switches SLEEP mode off and takes XT55 back to AT+CFUN=1, or activates XT55 temporarily without leaving the current SLEEP mode. Definitions of the state transitions described in Table 11: Quit = XT55 exits SLEEP mode and returns to AT+CFUN=1.
XT55 Hardware Interface Description Confidential / Preliminary 2) s mo b i l e GSM_RTS1 can be used to temporarily wake up XT55 for the time specified with the AT^SCFG command (default = 2s). Recommendation: In NON-CYCLIC SLEEP mode, you can set an RTC alarm to wake up XT55 and return to full functionality. This is a useful approach because, in this mode, the AT interface is not accessible. XT55_hd_v00.02 Page 51 of 116 17.03.
s XT55 Hardware Interface Description Confidential / Preliminary 3.
s XT55 Hardware Interface Description Confidential / Preliminary 3.8 mo b i l e RTC backup for GSM/GPRS part of XT55 The internal Real Time Clock of the XT55 GSM/GPRS part is supplied from a separate voltage regulator in the power supply ASIC which is also active when the GSM/GPRS part of the XT55 is in POWER DOWN status. An alarm function is provided that allows to wake up XT55 without logging on to the GSM network.
XT55 Hardware Interface Description Confidential / Preliminary 3.9 s mo b i l e Serial interfaces of the XT55 GSM/GPRS part The GSM/GPRS part of the XT55 module offers two unbalanced, asynchronous serial interfaces conforming to ITU-T V.24 protocol DCE signaling. The electrical characteristics do not comply with ITU-T V.28. The significant levels are 0V (for low data bit or ON condition) and 2.65V (for high data bit or OFF condition). For electrical characteristics please refer to Table 38.
s XT55 Hardware Interface Description Confidential / Preliminary 3.9.2 · · · · Features supported on the second serial interface of GSM/GPRS part (ASC1) 4-wire serial interface Includes only the data lines GSM_TXD1 and GSM_RXD1 plus GSM_RTS1 and GSM_CTS1 for hardware handshake. This interface is intended for voice calls, GPRS services and for controlling the GSM engine with AT commands. It is not suited for CSD calls, fax calls and Multiplex mode. On ASC1 no GSM_RING line is available.
s XT55 Hardware Interface Description Confidential / Preliminary 3.10 mo b i l e Audio interfaces XT55 comprises three audio interfaces available on the board-to-board connector: · Two analog audio interfaces, each with a balanced analog microphone input and a balanced analog earpiece output. The second analog interface provides a supply circuit to feed an active microphone. · Serial digital audio interface (DAI) using PCM (Pulse Code Modulation) to encode analog voice signals into digital bit streams.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e When shipped from factory, all audio parameters of XT55 are set to interface 1 and audio mode 1. This is the default configuration optimized for the Votronic HH-SI-30.3/V1.1/0 handset and used for type approving the Siemens reference configuration. Audio mode 1 has fix parameters which cannot be modified. To adjust the settings of the Votronic handset simply change to another audio mode.
XT55 Hardware Interface Description Confidential / Preliminary 3.10.2 s mo b i l e Speech processing The speech samples from the ADC or DAI are handled by the DSP of the baseband controller to calculate e.g. amplifications, sidetone, echo cancellation or noise suppression depending on the configuration of the active audio mode. These processed samples are passed to the speech encoder.
s XT55 Hardware Interface Description Confidential / Preliminary Note: mo b i l e Before starting the data transfer the clock GSM_SCLK should be available for at least three cycles. After the transfer of the LSB0 the clock GSM_SCLK should be still available for at least three cycles.
XT55 Hardware Interface Description Confidential / Preliminary 3.11 s mo b i l e SIM interface The baseband processor has an integrated SIM interface compatible with the ISO 7816 IC Card standard. This is wired to the host interface (board-to-board connector) in order to be connected to an external SIM card holder. Six pins on the board-to-board connector are reserved for the SIM interface. The GSM_CCIN pin serves to detect whether a tray (with SIM card) is present in the card holder.
XT55 Hardware Interface Description Confidential / Preliminary 3.11.1 s mo b i l e Requirements for using the GSM_CCIN pin According to ISO/IEC 7816-3 the SIM interface must be immediately shut down once the SIM card is removed during operation. Therefore, the signal at the GSM_CCIN pin must go low before the SIM card contacts are mechanically detached from the SIM interface contacts.
s XT55 Hardware Interface Description Confidential / Preliminary 3.11.2 mo b i l e Design considerations for SIM card holder The schematic below is a sample configuration that illustrates the Molex SIM card holder located on the DSB45 Support Box (evaluation kit used for type approval of the Siemens XT55 reference setup, see [7]). X503 is the designation used for the SIM card holder in [7].
s XT55 Hardware Interface Description Confidential / Preliminary 3.12 Control signals 3.12.1 Inputs mo b i l e Table 17: Input control signals of the GSM/GPRS part of the XT55 module Signal Pin Pin status Function Remarks Ignition GSM_IGT Falling edge Power up XT55 Left open or HiZ No operation Active low ³ 100ms (Open drain/collector driver to GND required in cellular device application).
XT55 Hardware Interface Description Confidential / Preliminary 3.12.2 Outputs 3.12.2.1 Synchronization signal s mo b i l e The synchronization signal serves to indicate growing power consumption during the transmit burst. The signal is generated by the GSM_SYNC pin. Please note that this pin can adopt two different operating modes which you can select by using the AT^SSYNC command (mode 0 and 1). For details refer to the following chapter and to [1].
XT55 Hardware Interface Description Confidential / Preliminary 3.12.2.2 s mo b i l e Using the GSM_SYNC pin to control a status LED As an alternative to generating the synchronization signal, the GSM_SYNC pin can be used to control a status LED on your application platform. To avail of this feature you need to set the GSM_SYNC pin to mode 1 by using the AT^SSYNC command. For details see [1]. When controlled from the GSM_SYNC pin the LED can display the functions listed in Table 18.
s XT55 Hardware Interface Description Confidential / Preliminary 3.12.2.3 mo b i l e Behavior of the GSM_RING0 line (ASC0 interface only) The GSM_RING0 line is available on the first serial interface (ASC0). The signal serves to indicate incoming calls and other types of URCs (Unsolicited Result Code). Although not mandatory for use in a host application, it is strongly suggested that you connect the GSM_RING0 line to an interrupt line of your application.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Table 19: ASC0 ring signal Function Pin Status Description Ring indication GSM_RING0 0 Indicates an incoming call or URC. If in NON-CYCLIC SLEEP mode CFUN=0 or CYCLIC SLEEP mode CFUN=5 or 6, the module is caused to wake up to full functionality. If CFUN=7 or 8, power saving is resumed after URC transmission or end of call. 1 No operation XT55_hd_v00.02 Page 67 of 116 17.03.
XT55 Hardware Interface Description Confidential / Preliminary 4 s mo b i l e GPS application interface The XT55 module integrates a GPS receiver which offers the full performance of GPS technology. The GPS receiver continuously tracks all satellites in view, thus providing accurate satellite position data. The GPS block can be used even if the XT55 module is deregistered from the GSM network. 4.
XT55 Hardware Interface Description Confidential / Preliminary 4.2 s mo b i l e Technical data Industry leading GPS performance · 12 channel GPS receiver · Signal acquisition using 1920 time / frequency search channels · Multipath-mitigation hardware · Cold start < 45 sec Low power · Typ.
XT55 Hardware Interface Description Confidential / Preliminary 4.3 s mo b i l e GPS operating modes Mode Function Normal operation The receiver is continuously running in normal Mode, as long as the operating voltage Vcc is supplied. Position fixes are generated at the maximum update rate. It is recommended to use an external backup battery to reduce the system start-up time.
XT55 Hardware Interface Description Confidential / Preliminary 4.3.1 s mo b i l e Trickle Power mode The default mode of XT55 GPS part is continuous mode, but the user can set the XT55 GPS part into the Trickle Power mode via input command message. The XT55 GPS part enters the trickle power mode corresponding to Figure 29 (800ms OFF Time and 200ms ON Time) as soon as valid GPS data are available. As a result the average power consumption is reduced by approximately 80 % (approximately 150mW).
XT55 Hardware Interface Description Confidential / Preliminary 4.3.2 s mo b i l e Comparision of Trickle Power and Push-to Fix mode A comparison of the Trickle Power and Push-to-Fix modes is shown in Figure below. This diagram shows that for position update intervals less than approximately 600 seconds (i.e. rates faster than one fix per 10 minutes), the Trickle Power mode at an update interval of 10 seconds offers a lower power solution.
XT55 Hardware Interface Description Confidential / Preliminary 4.4 s mo b i l e Power supply of the XT55 GPS part The power supply for the GPS part of the XT55 module has to be a single voltage source of VCC=3.3V ± 5%. It must be able to provide sufficient current of 250 mA. GPS_VCC: Two GPS_VCC pins of the board-to-board connector are dedicated to connect the power supply voltage, five GND pins shared with the GSM/GPRS part of the XT55 module are recommended for grounding; see Figure 42 for details.
XT55 Hardware Interface Description Confidential / Preliminary 4.6 s mo b i l e Serial interfaces of the XT55 GPS part The GPS part of the XT55 module offers two serial interfaces: SD1 · 2-wire serial interface · Includes the SDI1 (receive) and SDO1 (transmit) lines · Supported baud rate: 4800 bps. See also [2] for details on the used GPS protocol. SD2 · 2-wire serial interface · Includes the SDI2 (receive) and SDO2 (transmit) lines.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Vcc = 3.3 V DC 330 W GPS_RFPC0 BC817 47 k W GND Figure 31: Example of LED circuit 4.8 Receiver architecture The XT55 GPS receiver is a product that features the SiRFstarII-Low Power chipset. This complete 12 channel, WAAS-enabled GPS receiver provides a vastly superior position accuracy performance in a much smaller package.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e Figure 32 above shows the block diagram of the XT55 GPS receiver architecture. The GPS module is separated into four major parts: RF frequency down-converter, digital baseband demodulation, embedded ARM microprocessor and internal GPS software stored on-board (1 MBits) Flash-Memory.
XT55 Hardware Interface Description Confidential / Preliminary 4.10 s mo b i l e Start-up procedures The start-up strategy of the XT55 GPS part depends on the last position, current time and ephemeris data, that the receiver has stored no-board SRAM memory. There are three different start up procedures: 4.10.1 Coldstart The Coldstart take place when the receiver has no knowledge of its last position or time.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e 5 GSM and GPS antenna interfaces 5.1 GSM antenna installation The RF interface has an impedance of 50Ω. XT55 is capable of sustaining a total mismatch at the antenna connector or pad without any damage, even when transmitting at maximum RF power. The external antenna must be matched properly to achieve best performance regarding radiated power, DC-power consumption and harmonic suppression.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e The U.FL-R-SMT connector has been chosen as antenna reference point (ARP) for the Siemens reference equipment submitted to type approve XT55. All RF data specified throughout this manual are related to the ARP. For compliance with the test results of the Siemens type approval you are advised to give priority to the connector, rather than using the antenna pad. IMPORTANT: Both solutions can only be applied alternatively.
XT55 Hardware Interface Description Confidential / Preliminary 5.1.2 s mo b i l e GSM antenna pad The antenna can be soldered to the pad, or attached via contact springs. To help you ground the antenna, XT55 comes with a grounding plane located close to the antenna pad. The positions of both pads can be seen from Figure 52. When you decide to use the antenna pad take into account that the pad has not been intended as antenna reference point (ARP) for the Siemens XT55 type approval.
s XT55 Hardware Interface Description Confidential / Preliminary 5.3 mo b i l e Hirose antenna connector XT55 uses two ultra-miniature SMT antenna connectors (GSM and GPS antenna) supplied from Hirose Ltd. The product name is U.FL-R-SMT. The positions of both antenna connectors on the XT55 board can be seen in Figure 51. Figure 38: Mechanical dimensions of U.FL-R-SMT connector Table 21: Product specifications of U.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Table 22: Material and finish of U.FL-R-SMT connector and recommended plugs Part Material Finish Shell Phosphor bronze Silver plating Male centre contact Brass Gold plating Female centre contact Phosphor bronze Gold plating Insulator Plug: Receptacle: PBT LCP Black Beige Mating plugs and cables can be chosen from the Hirose U.FL Series. Examples are shown below and listed in Table 23.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e In addition to the connectors illustrated above, the U.FL-LP-(V)-040(01) version is offered as an extremely space saving solution. This plug is intended for use with extra fine cable (up to Æ 0.81 mm) and minimizes the mating height to 2 mm. See Figure 41 which shows the Hirose datasheet. Figure 41: Specifications of U.FL-LP-(V)-040(01) plug XT55_hd_v00.02 Page 83 of 116 17.03.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e Table 23: Ordering information for Hirose U.FL Series Item Part number HRS number Connector on XT55 U.FL-R-SMT CL331-0471-0-10 Right-angle plug shell for Æ 0.81 mm cable U.FL-LP-040 CL331-0451-2 Right-angle plug for Æ 0.81 mm cable U.FL-LP(V)-040 (01) CL331-053-8-01 Right-angle plug for Æ 1.13 mm cable U.FL-LP-066 CL331-0452-5 Right-angle plug for Æ 1.32 mm cable U.FL-LP-066 CL331-0452-5 Extraction jig E.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e 6 Electrical, reliability and radio characteristics 6.1 Absolute maximum ratings Absolute maximum ratings for supply voltage and voltages on digital and analog pins of XT55 are listed in Table 24. Exceeding these values will cause permanent damage to XT55. Table 24: Absolute maximum ratings (GSM/GPRS part) Parameter Min Max Unit Voltage GSM_BATT+ -0.3 4.8 V Voltage at digital pins -0.3 3.
XT55 Hardware Interface Description Confidential / Preliminary 6.3 s mo b i l e Pin description Please note that the reference voltages listed in Table 27 are the values measured directly on the XT55 module. They do not apply to the accessories connected. If an input pin is specified for VIHmax = 3.3V, be sure never to exceed the stated voltage. The value 3.3V is an absolute maximum rating. The Hirose DF12C board-to-board connector on XT55 is a 80-pin double-row receptacle.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e Table 27: Electrical description of application interface Function Signal name IO Signal form and level Comments GSM power supply GSM_BATT+ I VI = 3.3V to 4.8V VInorm = 4.2V Inorm ≈ 1.6A (during Tx burst) Imax< 2A Power supply input. 5 GSM_BATT+ pins to be connected in parallel. 5 GND pins to be connected in parallel. The power supply must be able to meet the requirements of current consumption in a Tx burst (up to 3A).
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Function Signal name IO Signal form and level Comments Ignition GSM_IGT I RI ≈ 100kW, CI ≈ 1nF VILmax = 0.5V at Imax = -20µA VOpenmax = 2.3V Input to switch the mobile ON. The line must be driven low by an Open Drain or Open Collector driver. ON Emergency shutdown (Watchdog) GSM_EMERGOFF I ~~~ |____| ~~~ Active Low ³ 100ms RI ≈22kW VILmax = 0.5V at Imax = -100µA VOpenmax = 2.
XT55 Hardware Interface Description Confidential / Preliminary Function Signal name s mo b i l e IO Signal form and level Comments I RI ≈ 100kW VILmax = 0.5V VIHmin = 2.15V at I = 20µA, VIHmax=3.3V at I = 30µA GSM_CCIN = high, SIM card holder closed (no card recognition) GSM_CCRST O RO ≈47W VOLmax = 0.25V at I = 1mA VOHmin = 2.3V at I = -1mA VOHmax = 2.73V GSM_CCIO IO RI ≈10kW VILmax = 0.5V VIHmin = 1.95V, VIHmax=3.3V Maximum cable length 200mm to SIM card holder.
Function Signal name s mo b i l e IO Signal form and level Comments Analog audio GSM_EPP2 interfaces GSM_EPN2 O VOmax = 3.7Vpp See also Table 32. The audio output is balanced and can directly operate an earpiece. If unused keep pins open. GSM_EPP1 O GSM_EPN1 O VOmax = 3.7Vpp See also Table 32. Explanation of signal names: P = positive, N = negative XT55 Hardware Interface Description Confidential / Preliminary Balanced audio output. Can be used to directly operate an earpiece.
s XT55 Hardware Interface Description Confidential / Preliminary Function Signal name mo b i l e IO Signal form and level Comments Digital Input / GPS_GPIO10 Output I/O CMOS 3.3V DC level See Chapter 4.5 Digital Input / GPS_GPIO13 Output I/O CMOS 3.3V DC level See Chapter 4.5 Digital Input / GPS_GPIO14 Output I/O CMOS 3.3V DC level See Chapter 4.5 Digital Input / GPS_GPIO15 Output I/O CMOS 3.3V DC level See Chapter 4.5 GPS Reset GPS_M-RST I CMOS 3.
s XT55 Hardware Interface Description Confidential / Preliminary 6.4 mo b i l e Power supply ratings Table 28: Power supply ratings (GSM/GPRS part) Parameter Description Conditions Min GSM_BATT+ Supply voltage Reference points on XT55: TP GSM_BATT+ and TP GND (see Figure 52). 3.3 Typ Max 4.2 Unit 4.8 V 400 mV Voltage must stay within the min/max values, including voltage drop, ripple, spikes.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Table 29: Power supply ratings (GPS part) Parameter Description Conditions GPS_VCC Supply voltage IGPS_VCC Average supply current XT55_hd_v00.02 Min 3.14 Continuous mode (without antenna feeding on GPS_VCC_RF) Page 93 of 116 Typ Max Unit 3.3 3.46 V 80 100 mA 17.03.
s XT55 Hardware Interface Description Confidential / Preliminary 6.5 mo b i l e Current consumption during GSM/GPRS transmit burst The diagrams provided in Figure 48 and Figure 49 illustrate the typical current consumption of the application caused during a transmit burst. The typical peak current is shown vs. the power control level for 900 MHz, 1800 MHz and 1900 MHz and vs. the return loss of the antenna. Test conditions: All measurements have been performed at Tamb= 25°C, VGSM_BATT+ nom = 4.1V.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Average Current DCS1800 (VBATT+=4.1V) 0.3 0.25 0.26 1 TX - Average Current 2 TX - Average Current Current (Amps) 0.2 0.19 0.15 0.18 0.16 0.14 0.13 0.13 0.1 0.12 0.10 0.10 0.05 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Power Control Level Figure 44: Typical current consumption vs. return loss in GSM 1800 network Average Current PCS1900 (VBATT+=4.1V) 0.3 0.29 0.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Burst Current GSM900 (VBATT+=4.1V) 1.8 1.6 1.6 1.4 1 TX - Peak current 1.2 Current (Amps) 1.24 1 0.8 0.6 0.68 0.4 0.4 0.3 0.2 0.28 0 5 7 9 11 13 15 17 19 Power Control Level Figure 46: Peak current consumption during transmit burst in EGSM 900 network Burst Current DCS1800 (VBATT+=4.1V) 1 0.9 0.8 1 TX - Peak current 0.84 Current (Amps) 0.7 0.6 0.5 0.52 0.4 0.38 0.3 0.27 0.2 0.24 0.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e Burst Current PCS1900 (VBATT+=4.1V) 1 0.92 0.9 0.8 1 TX - Peak current Current (Amps) 0.7 0.6 0.6 0.5 0.4 0.42 0.3 0.3 0.24 0.2 0.1 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Power Control Level Test conditions: Tamb= 25°C, VGSM_BATT+ nom = 4.1V Figure 48: Peak current consumption during transmit burst in GSM 1900 network XT55_hd_v00.02 Page 97 of 116 17.03.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e 1600 Service mode GSM900 ch.124 Variations in current with 0.4dB return loss (all phases) 1400 1200 Current (mA) 1000 ch.124 PCL5 800 600 400 200 0 Burst (max) Burst (min) Average Current (Max) Average Current (Min) 1000 Service mode PCS1900 ch.661 Variations in current with 0.6dB return loss (all phases) 900 800 700 Current (mA) 600 ch.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e 6.6 Electrical characteristics of the voiceband part 6.6.1 Setting audio parameters by AT commands The audio modes 2 to 6 can be adjusted according to the parameters listed below. Each audio mode is assigned a separate set of parameters. Table 30: Audio parameters adjustable by AT command Parameter Influence to Range Gain range Calculation inBbcGain MICP/MICN analog amplifier gain of baseband controller before ADC 0...
s XT55 Hardware Interface Description Confidential / Preliminary 6.6.2 mo b i l e Audio programming model The audio programming model shows how the signal path can be influenced by varying the AT command parameters. The model is the same for all three interfaces, except for the parameters and which cannot be modified if the digital audio interface is being used, since in this case the DAC is switched off. The parameters inBbcGain and inCalibrate can be set with AT^SNFI.
s XT55 Hardware Interface Description Confidential / Preliminary 6.6.3 mo b i l e Characteristics of audio modes The electrical characteristics of the voiceband part depend on the current audio mode set with the AT^SNFS command. Table 31: Voiceband characteristics (typical) Audio mode no.
s XT55 Hardware Interface Description Confidential / Preliminary 4) mo b i l e Audio mode 5 and 6 are identical. With AT^SAIC, you can easily switch mode 5 to the second interface. Therefore, audio mode 6 is only kept for compatibility to earlier Siemens GSM products. Note: With regard to acoustic shock, the cellular application must be designed to avoid sending false AT commands that might increase amplification, e.g. for a high sensitive earpiece.
s XT55 Hardware Interface Description Confidential / Preliminary 6.6.5 mo b i l e Voiceband transmit path Test conditions: · The values specified below were tested to 1kHz and 0dB gain stage, unless otherwise stated. · Parameter setup: Audio mode = 5 for GSM_MICP1 to GSM_MICN1 and 6 for GSM_MICP2 to GSM_MICN2, inBbcGain= 0, inCalibrate = 32767, outBbcGain = 0, OutCalibrate = 16384, sideTone = 0 Table 33: Voiceband transmit path Parameter Min Typ Input voltage (peak to peak) Max Unit 1.
s XT55 Hardware Interface Description Confidential / Preliminary 6.7 mo b i l e Air interface of the XT55 GSM/GPRS part Test conditions: All measurements have been performed at Tamb= 25°C, VGSM_BATT+ nom = 4.1V. The reference points used on XT55 are the GSM_BATT+ and GND contacts (test points are shown in Figure 52).
s XT55 Hardware Interface Description Confidential / Preliminary 6.8 mo b i l e Electrostatic discharge The GSM engine is not protected against Electrostatic Discharge (ESD) in general. Consequently, it is subject to ESD handling precautions that typically apply to ESD sensitive components. Proper ESD handling and packaging procedures must be applied throughout the processing, handling and operation of any application that incorporates a XT55 module.
XT55 Hardware Interface Description Confidential / Preliminary 6.9 s mo b i l e Reliability characteristics The test conditions stated below are an extract of the complete test specifications. Table 36: Summary of reliability test conditions Type of test Conditions Standard Vibration Frequency range: 10-20 Hz; acceleration: 3.
XT55 Hardware Interface Description Confidential / Preliminary 7 s mo b i l e Mechanics The following chapters describe the mechanical dimensions of XT55 and give recommendations for integrating XT55 into the host application. 7.1 Mechanical dimensions of XT55 Figure 51 shows the top view of XT55. For further details see Figure 53. Size: Weight: 35.0 ± 0.15mm x 53.0 ± 0.15mm x 5.1 ± 0.
s XT55 Hardware Interface Description Confidential / Preliminary 35.00 mo b i l e Board-to-board connector ±0.15 3.0 ±0.2 3.5 3.6 3) 0.85 ±0.1 17.5 2) ø2.05 GSM_BATT+ +0.01 -0.04 Antenna pad 2.6 6.6 Identification label GSM 5.10 Ground ±0.2 3.2 1.1 1.6 1) max. ø 3 mm mounting area 2) max. ø 3,2 mm mounting area 1.1 1.5 1.9 1.4 5.2 12.3 0.5 2.4 4.6 1) 9.5 2.0 +0.1 Identification label GPS Ground 53.0 2.0 ± 0.15 20.2 19.2 14.7 2.3 3.3 2.5 2.5 2.3 3-LEFT 3.
XT55 Hardware Interface Description Confidential / Preliminary 7.2 s mo b i l e Mounting XT55 onto the application platform There are many ways to properly install XT55 in the host device. An efficient approach is to mount the XT55 PCB to a frame, plate, rack or chassis. Fasteners can be M1.6 or M1.8 screws plus suitable washers, circuit board spacers, or customized screws, clamps, or brackets. Screws must be inserted with the screw head on the bottom of the XT55 PCB.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e Figure 55: Recommended dowel XT55_hd_v00.02 Page 110 of 116 17.03.
s XT55 Hardware Interface Description Confidential / Preliminary 7.3 mo b i l e Board-to-board connector This chapter provides specifications for the 80-pin board-to-board connector which serves as physical interface to the host application. The receptacle assembled on the XT55 PCB is type Hirose DF12C. Mating headers from Hirose are available in different stacking heights. Table 37: Ordering information DF12 series Item Part number Stacking height (mm) HRS number Receptacle on XT55 DF12B(3.
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e Figure 56: Mechanical dimensions of Hirose DF12 connector XT55_hd_v00.02 Page 112 of 116 17.03.
s XT55 Hardware Interface Description Confidential / Preliminary mo b i l e 8 Reference approval 8.1 Reference equipment for type approval The Siemens reference setup submitted to type approve XT55 consists of the following components: · Siemens XT55 cellular engine · Development Support Box (DSB45) · Flex cable (160 mm) from Hirose DF12C receptacle on XT55 to Hirose DF12 connector on DSB45. Please note that this cable is not included in the scope of delivery of DSB45.
XT55 Hardware Interface Description Confidential / Preliminary 8.2 s mo b i l e Compliance with FCC Rules and Regulations The FCC Equipment Authorization Certification for the reference application described in Chapter 8.1 is listed under the FCC identifier QIP granted to Siemens AG. The reference application registered under the above identifier is certified to be in accordance with the following Rules and Regulations of the Federal Communications Commission (FCC).
s XT55 Hardware Interface Description Confidential / Preliminary 9 mo b i l e List of parts and accessories Table 39: List of parts and accessories Description Supplier Ordering information XT55 module Siemens Siemens ordering number: L36880-N8380-A100 Siemens Car Kit Portable Siemens Siemens ordering number: L36880-N3015-A117 DSB45 Support Box Siemens Siemens ordering number: L36880-N8301-A100 BB35 Bootbox Siemens Siemens ordering number: L36880-N8102-A100-1 Votronic Handset VOTRONIC
XT55 Hardware Interface Description Confidential / Preliminary s mo b i l e Table 40: Molex sales contacts (subject to change) Molex Molex Deutschland GmbH American Headquarters For further information please click: Felix-Wankel-Str. 11 4078 Heilbronn-Biberach Germany Lisle, Illinois 60532 U.S.A. http://www.molex.com/ Phone: +49-7066-9555 0 Fax: +49-7066-9555 29 Email: mxgermany@molex.com Molex China Distributors Beijing, Room 1319, Tower B, COFCO Plaza No.
