Telit Wireless Solutions 1vv0300773a manual 1.1 + 5V input Source Power Supply Design Guidelines

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GE863-PRO3Hardware User Guide

1vv0300773a Rev. 0 - 24/01/08

5.4.1.1 + 5V input Source Power Supply Design Guidelines

•The desired output for the power supply is 3.8V, hence there's not a big difference between the input source and the desired output and a linear regulator can be used. A switching power supply will not be suited because of the low drop out requirements.

•When using a linear regulator, a proper heat sink shall be provided in order to dissipate the power generated.

•A Bypass low ESR capacitor of adequate capacity must be provided in order to cut the current absorption peaks close to the GE863-PRO3, a 100μF tantalum capacitor is usually suited.

•Make sure the low ESR capacitor on the power supply output (usually a tantalum one) is rated at least 10V.

•A protection diode should be inserted close to the power input, in order to save the GE863-PRO3from power polarity inversion.

An example of linear regulator with 5V input is:

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Contents GE863-PRO3Hardware User Guide Contents GE863-PRO 3 Hardware User Guide This document is relating to the following products Disclaimer Overview Length 41,4 mm Width 31,4 mm Thickness 3,6 mm GE863-PRO3Mechanical DimensionsTelit GE863-PRO3module overall dimension are GE863-PRO3module connections C11 Simrst C12 Simio D1 Charge D2 VAUX1 DTE GPIO7 / Rftxdisable GSMC2 Vbatt C3 Vrtc D10 GND D11 Simvcc D12 Simclk E1 GND E2 PwrmonPB9 Nrst Reset ARMPB8 ON/OFF*-APPB1 PB0PB2 PB7XOUT32 HdmbXIN32 PA3VBATT2 Reserved GNDBalls Layout ARM Port IO multiplexing ARM PIO Controller a multiplexingARM PIO Controller B multiplexing ARM PIO Controller C multiplexing Hardware Commands Turning on the GE863-PRO3GSM/GPRS Engine10k +1,8/5Hardware shutdown Hardware Unconditional Reboot of GSM/GPRS Engine2Turning OFF the GE863-PRO3GSM/GPRS Engine Turning ON/OFF the GE863-PRO3ARM ON/OFF*-AP # GND AT+CFUN=1 Power Supply GSM Power Supply Requirements AT+CFUN=4ARM Power Supply Requirements Vrtc Backup supplySuggested circuit is General Design RulesElectrical design Guidelines 817A19A Seiko1.1 + 5V input Source Power Supply Design Guidelines 1.2 + 12V input Source Power Supply Design Guidelines Battery Source Power Supply Design Guidelines Battery Charge control Circuitry Design Guidelines GE863-PRO3Hardware User Guide Thermal Design Guidelines Power Supply PCB layout Guidelines Antenna GSM Antenna RequirementsGSM Antenna PCB line Guidelines 50 ohmGSM Antenna installation Guidelines Electro Magnetic Interference GuidelinesOperating Range Interface levels Cmos Level Min Max Logic level specificationsAbsolute Maximum Ratings -Not Functional Parameter Min Max Cmos 1.8V-A Current characteristics Level Typical GSM Gpio Current characteristics Level TypicalCmos 3.1V Current characteristics Level Typical Operating Range Interface levels Cmos Vrtc Level Min MaxSignal Min Max Signal FunctionPhone reset Serial Ports Modem Serial Port Modem Serial Port 2 DebugSignals of the GE863-PRO3GSM/GPRS engine serial port are RS232 level translation An example of level translation circuitry of this kind is GE863-PRO3Hardware User Guide Audio Section Overview Input Lines Microphone Short descriptionInput Lines Characteristics Micmt 1st differential microphone pathOutput Lines Speaker Output Lines Characteristics Earmt Differential Line-out Drivers PathEvaluation Kit for Telit GE863- PRO3 Modules 10 GSM/GPRS General Purpose I/O ON/OFFUsing the RF Transmission Control GPIO7 Using a Gpio Pad as InputUsing a Gpio Pad as Output 10.4Using the Rftxmon Output GPIO3Using the Alarm Output Using the Buzzer Output GPIO4Device Status 10.7Indication of network service availabilityLED status RTC Bypass out 10.9VAUX1 power outputOperating Range VAUX1 power supply Stencil Mounting the GE863-PRO3on the Application Board11.1General PCB pad DesignSolder paste 11.1.4 GE863-PRO3Solder Reflow Following is the recommended solder reflow profile3C/second max Packing System Section A-AModules orientation on tray Moisture Sensibility Conformity Assessment Issues Safety Recommandations Document Change Log Revision Date Changes
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