Telit Wireless Solutions GM862-GPS инструкция обслуживания

GM862-GPS Hardware User Guide GM862-GPS HW User Guide 1vv0300728 Rev. 0 - 27/04/06[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 2 of 55 Contents 1 Overview ....................................................................................................................... .... 4 2 Hardware Co mmands .......[...]

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GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 4 of 55 1 Overview The aim of this document is the description of some h a rdware solutions u seful fo r developi ng a product with the Telit GM862-GPS modules . In this document all [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 5 of 55 2 Hardware Commands 2.1 Turning ON the GM862-GPS To turn on the GM862-GPS the pin ON# must be tied low for at least 1 second and then released. The maximum current that can be[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 6 of 55 For example: 1- Let's assume you need to drive the ON# pin with a totem pole output of a +3/5 V microcontroller (uP_OUT1): 2- Let's assume you need to drive the ON# [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 7 of 55 2.2 Turning OFF the GM862-GPS The turning off of the device can be done in two ways: • by software command (see GM862-GPS Software User Guide) • by hardware shutdown When [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 8 of 55 2.2.2 Hardware Unconditional Reboot To unconditionally Reboot the GM862-GPS the pi n RESET# must be tied low for at least 200 milliseconds and then released. The maximum curre[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 9 of 55 For example: 1- Let's assume you need to drive the RESET# pin with a totem pole output of a +3/5 V microcontroller (uP_OUT2): The hardware unconditional reboot must not b[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 10 of 55 3 Power Supply The power supply circuitry and board layout are the most important part in the full product design and they strongly reflect on the product overall perfo rmanc[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 11 of 55 3.2 General Design Rules The principal guidelines for the Power Supply Design embrace three different design steps: - the electrical design - the thermal design. - the PCB la[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 12 of 55 An example of linear regulator with 5V input is:[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 13 of 55 3.2.1.2 + 12V input Source Power Supply Design Guidelines • The desired output for the power supply is 3.8V, hence due to the big difference between the inpu t source and t[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 14 of 55 An example of switching regulator with 12V input is: 3.2.1.3 Battery Source Power Supply Design Guidelines • The desired nominal output for the power supply is 3.8V and the[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 15 of 55 3.2.1.4 Battery Charge control Circuitry Design Guidelines The charging process for Li-Ion Batteries can be divided into 4 phases: • Qualification and trickle charging • [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 16 of 55 As you can see, the charging process is not a tr ivial task to be done; moreover all these operations should start only if battery temperature is inside a charging range, usu[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 17 of 55 3.2.2 Thermal Design Guidelines The thermal design for the power supply heat sink should be done with the following specifications: • Average current consumption during tra[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 18 of 55 3.2.3 Power Supply PCB layout Guidelines As seen on the electrical design guidelines the pow er supply shall have a low ESR capacitor on the output to cut the current peaks a[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 19 of 55 4 Serial Ports The serial port on the Telit GM862-GPS is the core of the interface between the module and OEM hardware. 2 serial ports are available on the module: • MODEM [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 20 of 55 The signals of the GM862-GPS MODEM serial port are: RS232 Pin Number Signal GM862- GPS Pin Number Name Usage 1 DCD - dcd_uar t 36 Data Carrier Detect Output from the GM862-GP[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 21 of 55 Signal GM862- GPS Pin Number Name Usage RX_GPS 41 GPS Transmit line Output line of GPS serial Port ( NMEA protocol) TX_GPS 35 GPS Receive line Input line of GPS serial Port ([...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 22 of 55 An example of level translation circuitry of this kind is: the RS232 serial port lines are usually connected to a DB9 connector with the following layout:[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 23 of 55 4.2 5V UART level translation If the OEM application uses a microcontroller with a serial port (UART) that works at a voltage different from 2.8 - 3V, then a circuitry has to[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 24 of 55 NOTE: The UART input line TXD (rx_uart) of the GM862-GPS is NOT internally p ulled up with a resistor, so there may be the need to place an external 47 K Ω pull-up resistor[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 25 of 55 5 Audio Section Overview The Base Band Chip of the GM862-GPS Telit Module provides two different audio blocks; both in transmit ( Uplink ) and in receive ( Downlink ) directi[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 26 of 55 Ear_MT- Ear_MT+ +20dB 365mV rms Mic_MT+ Mic_MT- 7cm GM86 2-GPS Differential Line-Out Drivers Fully Differential Power Buff ers EXTERNAL AMPLIFIER -12dBFS 16 8 -45dBV/Pa 3,3mV[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 27 of 55 5.1 Microphone paths charac teristic and requirements TIP: being the microphone circuitry the more noise sensitive , its design and layout must be done with particular care. [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 28 of 55 TIP: definition of the nominal sensitivity of the microphone lines . The nominal sensitivity of the microphone lines i ndicates the voltage level on the GM862-GPS pins presen[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 29 of 55 TIP: environment consideration . For hands-free/car kit microphone, you must take into account the voice attenuation, due to the distance between the microphone itself and th[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 30 of 55 5.2 General Design Rules There are several configurations for the audio paths, but the most effective difference is between balanced and unbalanced microphone configuration. [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 31 of 55 5.4 Microphone Biasing The electret microphones usually need a biasing voltage to work properly. Refer to your microphone provider for the characteristics required. NOTE: The[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 32 of 55 NOTE: The cable to the microphone should not be shielded, instead a twisted pair cable shall be used. NOTE: The microphone sensitivity changes with the value of R2 and R3. Us[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 33 of 55 NOTE: In the unbalanced application the capacitor C3 shall be > 200nF otherwise the frequency response will be cut at low band frequencies (down to 300Hz). This capacitor [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 34 of 55 5.5 Microphone buffering As seen previously, a microphone shall be connected to the input pins of the GM862-GPS through a buffer amplifier that boosts the signal level to the[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 35 of 55 The buffer gain is given by the formula: 607 606 605 604 R R R R Gain = = The C636 and C637 capacitors are placed in order to cut off the gain at higher frequencies than the [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 36 of 55 5.5.2 Buffered Unbalanced (Single Ended) Microphone . The above schematic can be used for a single ended ( buffere d unbalanced ) microphone ; the required biasing circuitry [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 37 of 55 The buffer bandwidth at -3dB shall be 4KHz. Note that the biasing of the operational amplifier is given for the inverting amplifier by the series divider R714-R715. The 100nF[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 38 of 55 C726 = 1/ (2 π *4000*R719)= 7.10 *10 -9 F C727 = 1/ (2 π *4000*R711)= 2,65 *10 -9 F modified in 6,8nF (f c1 =4181Hz ) and 2,7nF (f c2 =3931Hz) because of co mmercial values[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 39 of 55 6 OUTPUT LINES (Speaker) 6.1 Short description. The Telit GM862-GPS provides two audio paths in receive section. Only one of the two paths c an be active at a time, selectabl[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 40 of 55 6.2 Output lines characteristics . “Ear_MT” Differential Line-out Drivers Path • line coupling: DC • line type: bridged • output load resistance : ≥ 14 Ω • in[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 41 of 55 6.3 General Design rules There are several configurations for the audio output path, but the variou s design requirements can be grouped into three different categories: • [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 42 of 55 6.4 Handset earphone design As seen previously, a 16 Ω earpiece can be directly connected to the output pads EAR_MT+ and EAR_MT- of the GM862-GPS . This solution is often t[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 43 of 55 The resulting gain and high pass cut can be obta ined with the formula: 2 3 R R Gain = 4 * 3 * 2 1 . C R freq π = [Hz] And an example of internal Ear amplifier could be : So[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 44 of 55 6.6 Car Kit speakerphone design For the car kit speaker phone function the power output requirement is usually at least 4W, therefore an amplifier is needed to boost the GM86[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 45 of 55 7 General Purpose I/O The general purpose I/O pins can be configured to act in three different ways: - input - output - alternate function (internally controlled) Input pins [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 46 of 55 7.3 Using the Alarm Output GPIO6 The GPIO6 pin, when configured as Alarm Outpu t, is controlled by the GM862-GPS module and will rise when the alarm starts and fall after the[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 47 of 55 8 GPS Receiver 8.1 GPS Antenna The GE863-GPS module is not provided with an internal LNA amplifier. The use of an active antenna is suggested to achieve a good performance. T[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 48 of 55 9 Camera 9.1 Camera Transchip The GM862-GPS provides a direct support for Transchip digital cameras with the following characteristics: 9.1.1 Camera interface connectors The [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 49 of 55 n.c 13 DOUT_6 I/O n.c 14 DOUT_7 I/O n.c 15 DOUT_8 I/O n.c 16 VCLKOUT O n.c 17 VALIDH O n.c 18 VALIDV O 50 GPIO7 CAM_PWR_ON O External 2.8V Regulator enable controlled by CAM_[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 50 of 55 Camera Socket Connector 9.1.3[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 51 of 55 EVB for Transchip camera support In order to interface the Telit GM862 with a CMOS camera, Telit has developed an ev aluation board. The EVK allow connecting all Telit module[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 52 of 55 9.1.4 Block Diagram for supported camera DVDD is an external power supply of 2.8V, controlled or gated by pin CAM_PWR_ON. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 2[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 53 of 55 9.1.5 Schematic Diagrams for supported cameras[...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 54 of 55 9.1.6 Example usage script for camera Camera setting: (shown here are the defaults ones) >AT#CAMSEL=0 (camera selection: 0-auto, 1-agilent, 2-transchip) OK >AT#CMODE=0 [...]

GM862-GPS Hardware User Guide 1vv0300728 Rev. 0 - 27/04/06 Reproduction forbidden without Telit Communications S.p.A. writte n authorization - All Right reserved page 55 of 55 10 Document Change Log R R e e v v i i s s i i o o n n D D a a t t e e C C h h a a n n g g e e s s ISSUE#0 27/04/06 Release First ISSUE# 0[...]