GM 47/GM 48 Design Guidelines
CE The product described in this manual conforms to the TTE directive 91/263/EEC and EMC directive 89/336/EEC. The product fulfils the requirements according to ETS 300 342-1. The information contained in this document is the proprietary information of Sony Ericsson Mobile Communications.
GM47/48 Design Guidelines Contents 1 INTRODUCTION ...........................................................................................................5 1.1 1.2 1.3 2 MECHANICAL INTEGRATION.......................................................................................7 2.1 3 OVERVIEW ...............................................................................................................5 PRECAUTIONS ..................................................................................
GM47/48 Design Guidelines APPENDIX III GSM TRANSMIT WAVEFORM CHARACTERISTICS.....................................
GM47/48 Design Guidelines 1 Introduction 1.1 Overview The GM47/48 belong to a new generation of Sony Ericsson Mobile Communications GSM modules. This document describes the main characteristics and functionality of the GM 47/48, two dual band products for 900/ 1800 MHz and 850/1900 MHz GSM bands respectively.
GM47/48 Design Guidelines MO Mobile Originated MS Mobile Station MT Mobile Terminated PCM Pulse Code Modulation PDU Protocol Data Unit RLP Radio Link Protocol RF Radio Frequency RTC Real Time Clock SDP Service Discovery Protocol SMS Short Message Service SIM Subscriber Identity Module TBD To Be Defined BA/SEM/MSC 02:0006 Rev PA1 6
GM47/48 Design Guidelines 2 Mechanical Integration The GM 47/48 are protected with AISI 304 Stainless Steel covers suitable to fulfil the environmental and EMC requirements. Dimensions, the position of the different connectors and mounting holes are shown in figure 2.1. 2.1 Physical Dimensions Figure 2.
GM47/48 Design Guidelines 3 Electrical Integration 3.1 General The electrical connections to the module (except the antenna), are set through the System Connector Interface. The connector shall allow the following connections: board to board and board to cable. See section 5 for suppliers and part numbers. The figure 3.1 below indicates the pin numbering scheme. Figure 3.1 GM 47/48.
GM47/48 Design Guidelines 3.2 Grounding Pins Name Description 2, 4, 6, 8, 10, 12 DGND Digital Ground 60 AGND Analogue Ground There are two ground signals in GM 47/48, Analogue Ground (AGND) and Digital Ground (DGND). The analogue Ground is connected to pin number 60, and the Digital Ground is connected to the System Connector Interface through pin numbers 2, 4, 6, 8, 10 and 12. Note: All the Ground pins have to be connected to the application.
GM47/48 Design Guidelines 3.3 External Supply to Module Pins Name Description 1, 3, 5, 7, 9, 11 VCC Regulated Power Supply Connect all of the pins together in the application in order to carry the current drawn by the module. 3.3.1 Power Supply (VCC) The VCC supplies the module with external power. Any other voltage needed is generated internally. Parameter Mode Limit Voltage to be applied Nominal 3.6 Volts Tolerance 3.4 Volts - 4.
GM47/48 Design Guidelines 3.3.2 General Recommendations The power supply conditions for the GM47/48 Vcc connection are as follows: Maximum voltage drop during transmit burst Maximum Ripple 200mV TBD : [estimate 50mV] Table 3.
GM47/48 Design Guidelines CBULK ESR = 50mΩ RLINE = 200mΩ PSU LIMIT CBULK (min) ≥ 2.0 Amp 1.5 Amp 1.0 Amp 0.5 Amp 6000µF 6000µF 6000µF *12000µF Transmit Burst Vcc Dip (approx) 200mV 190mV 190mV 200mV Table 3.5 Note: When this capacitance is used with the PSU conditions stated, the PSU will reach current limit.
GM47/48 Design Guidelines 3.4 SIM connections All track lengths between the SIM card and the module must be kept below 15cm. This is due to the voltage drop/capacitance associated with the extra track length and it has type approval issues as it will affect timing. This is primarily designed as a 3 Volts SIM interface, but if a 5 Volts SIM card is connected to it the interface will automatically detect this and adjust the appropriate parameters. SIM connections are shown below. Figure 3.
GM47/48 Design Guidelines 3.5 Audio Connections Audio connections for both of the analogue paths are shown below. 3.5.1 Analogue Audio Pin Signal Dir. Description 57 AFMS O Audio From Mobile Station 59 ATMS I Audio To Mobile Station 60 AGND - Ground (return) for analogue audio ATMS and AFMS are the audio input and output for the module. Figure 3.3 shows the connection of the analogue audio signals ATMS and AFMS to the CODEC.
GM47/48 Design Guidelines will be used by audio accessories like handsets or Hands Free equipment. • Portable Hands Free - This state activates a different amplification factor in the GM47 and activates a microphone bias level of 2V in ATMS when a call is in progress. This is the default state at power-on. .
GM47/48 Design Guidelines AFMS is the analogue audio output from the module. When it is active, the output is derived from the PCM digital audio by the decoder part of the CODEC. The PCM data comes from PCMI on the system connector. It is also used as an ear-piece driver for the Portable Hands Free accessory. Zout4 (0.3 – 3.5 kHz) ≅ 120 Ω Output capacitance 2.2 µF 5 Levels (THD<5%) Drive capability into 5 kΩ (0.3 – 3.5 kHz) > 2.4 Vpp [TBC] Drive capability into1.5 kΩ (0.3 – 3.5 kHz) > 2.
GM47/48 Design Guidelines 3.7 Interfacing to a 3.3V µProcessor Although the inputs to the modules can withstand a certain degree of over voltage they should not be purposefully driven at a higher voltage than that quoted in the pin out in appendix II. This particularly applies to the serial com ports used to send and receive the commands to and from the module. Level shifting I/C’s are required to interface to the module.
GM47/48 Design Guidelines 4 Developers Board The developers board is the reference design against which the module has been type approved, the circuit diagram for this is available upon request from customer support 4.1 Power Circuit A 3A simple switcher step down voltage regulator has been used to produce the module Vcc. Two 6800µF capacitors are located adjacent to the module to cope with the GSM current pulses. The capacitors are low ESR type approximately 16mΩ. 4.
GM47/48 Design Guidelines 4.5 EMC The circuit ground is bonded to the metal chassis of the developers kit box, all signal connections are filtered via ferrite chokes. 4.6 Data signals: The data and handshake lines are converted between 2.7V & 5V logic and then between 5V & RS232 levels. The data signal and handshake lines into the module are powered from the VIO supply interface which ensures isolation of the signal when the module is off. Diodes D3-5,D7 & D8 are not fitted.
GM47/48 Design Guidelines 5 Part numbers 5.1 System connector A connector that can be used to interface to the system connector is the Samtech FLE or SFMC or CLP series, the female part number is CLP130-02-F-D. This connector or an equivalent can be sourced from imperial connectors below, again this company is just an example of one supplier. 5.2 RF connector MMCX is a standard RF connector and should be able to be sourced from most suppliers. 5.
GM47/48 Design Guidelines System connector For the system connector follow http://www.imperial-connect.co.uk/products/prodprofile127.html click on ITRQPGA thumbnail. 5.4.2 IMS connectors Connector cables from MMCX to SMA can be ordered from this supplier normally with a 2-3 week lead time.
GM47/48 Design Guidelines 6 Type Approval The system integrator has to get CE marking for the integrated solution with the GSM module in Europe (GM47) and the FCC approval in the US (GM48). The system integrator only has to show compliance with the essential requirements of the module by the integration of it into the application.
GM47/48 Design Guidelines 6.3 SIM Testing SIM testing does not need to be carried out since it is a passive component. Points to note regarding the implementation of the SIM card holder are as follows. • • 6.4 SIM presence must be implemented to comply with the module approval conditions. Any manufacturers SIM card holder can be used and this can also be either 6 or 8 pins.
GM47/48 Design Guidelines 6.6 SAR warning If the application is using an antenna which is less than 20cm away from the any part of the users body, integrators are legally obliged to publish SAR figures for the product. This testing would need to be carried out by the system integrator. Even if SAR measurements are not required it is considered good practice to insert a warning in any manual produced indicating it is a radio product and that care should be taken. 6.7 Other TA issues 6.7.
GM47/48 Design Guidelines Appendix I - Technical Data Mechanical specifications Maximum length: 50 mm Maximum width: 33 mm Maximum thickness: 6.82 mm (without system connector pins length) Weight: 18,5 g Power supply voltage, normal operation Voltage: 3.6V Nominal Tolerance ±0.2V Ripple: <100mV @ 200KHz, <20mV @>200KHz Voltage must always stay within a normal operating range, ripple included.
GM47/48 Design Guidelines Shock response spectrum II, peak acceleration: - 3 shocks in each axis and direction: 1000 m/s2, 6 ms Bump: Acceleration 250 m/s2 Free fall transportation: 1.
GM47/48 Design Guidelines Appendix II – GM47/48 Pin out Pin Signal Name Dir Signal Type Description 1. VCC - Supply Power Supply 2. DGND - - Digital Ground 3. VCC - Supply Power Supply 4. DGND - - Digital Ground 5. VCC - Supply Power Supply 6. DGND - - Digital Ground 7. VCC - Supply Power Supply 8. DGND - - Digital Ground 9. VCC - Supply Power Supply 10. DGND - - Digital Ground 11. VCC - Supply Power Supply 12. DGND - - Digital Ground 13.
GM47/48 Design Guidelines 32. TIMESTAMP O Dig. 2.75 Timestamp Timestamp is reserved for future use, if AGPS is implemented on network side. 33. LED O Dig. 2.75 Flashing LED 34. VIO O Power Out 2.75 Module powered indication. The VIO is a 2.75 V output that could power external devices to transmit data towards the GSM device to a 75mA max. 35. TX_ON O Dig 2.75 This output shall indicate when the GSM module is going to transmit the burst. 36. RI O Dig. 2.75 Ring Indicator 37.
GM47/48 Design Guidelines 56. BEARN O Analogue Speaker output negative 57. AFMS O Analogue Audio output from module 58. SERVICE I 12V/2.7V Flash programming voltage for the MS. Enable logger information if no flashing Former VPPFLASH 59. ATMS I Analogue Audio input to module 60.
GM47/48 Design Guidelines Appendix III GSM transmit waveform characteristics The simplified GSM loading characteristics and power supply reference model in relation to the GM47 system connector is represented in figure 1. J1 represents the interface to the GM47 system connector and the voltage there is referenced Vcc. Figure 2 shows a 1:8 cycle with the receive burst occurring in timeslot 1 and transmit in timeslot 6. Some of the quiet period is used by the module to ‘listen’ to other GSM base-stations.
GM47/48 Design Guidelines 577 µs TRANSMIT A G GM47 Vcc F B E C D Figure 2 - Transmit Burst Vcc Waveform A. The sharp fall in voltage in this region is caused by the ESR of the capacitors (mounted as close to the module Vcc pins as possible. B. The RC discharge is controlled by CBULK, RLINE, and RTX. C. If the PSU cannot supply the 2A max load of the GM47 and current limit is reached the discharge of CBULK goes linear.
