Telit Wireless Solutions 1vv0300773a manual Battery Charge control Circuitry Design Guidelines

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GE863-PRO3Hardware User Guide

1vv0300773a Rev. 0 - 24/01/08

•The battery capacity must be at least 500mAh in order to withstand the current peaks of 2A; the suggested capacity is from 500mAh to 1000mAh.

5.4.1.4 Battery Charge control Circuitry Design Guidelines

The charging process for Li-Ion Batteries can be divided into 4 phases:

•Qualification and trickle charging

•Fast charge 1 - constant current

•Final charge - constant voltage or pulsed charging

•Maintenance charge

The qualification process consists in a battery voltage measure, indicating roughly its charge status. If the battery is deeply discharged, that means its voltage is lower than the trickle charging threshold, then the charge must start slowly possibly with a current limited pre-charging process where the current is kept very low with respect to the fast charge value: the trickle charging.

During the trickle charging the voltage across the battery terminals rises; when it reaches the fast charge threshold level the charging process goes into fast charge phase.

During the fast charge phase the process proceeds with a current limited charging; this current limit depends on the required time for the complete charge and from the battery pack capacity. During this phase the voltage across the battery terminals still raises but at a lower rate.

Once the battery voltage reaches its maximum voltage then the process goes into its third state: Final charging. The voltage measure to change the process status into final charge is very important. It must be ensured that the maximum battery voltage is never exceeded, otherwise the battery may be damaged and even explode. Moreover for the constant voltage final chargers, the constant voltage phase (final charge) must not start before the battery voltage has reached its maximum value, otherwise the battery capacity will be highly reduced.

The final charge can be of two different types: constant voltage or pulsed. GE863-PRO3uses constant voltage.

The constant voltage charge proceeds with a fixed voltage regulator (very accurately set to the maximum battery voltage) and hence the current will decrease while the battery is becoming charged. When the charging current falls below a certain fraction of the fast charge current value, then the battery is considered fully charged, the final charge stops and eventually starts the maintenance.

The pulsed charge process has no voltage regulation, instead the charge continues with pulses. Usually the pulse charge works in the following manner: the charge is stopped for some time, let's say few hundreds of ms, then the battery voltage will be measured and when it drops below its maximum value a fixed time length charging pulse is issued. As the battery approaches its full charge the off time will become longer, hence the duty-cycle of the pulses will decrease. The battery is considered fully charged when the pulse duty-cycle is less than a threshold value, typically 10%, the pulse charge stops and eventually the maintenance starts.

The last phase is not properly a charging phase, since the battery at this point is fully charged and the process may stop after the final charge. The maintenance charge provides an additional charging process to compensate for the charge leak typical of a Li-Ion battery. It is done by issuing pulses with a fixed time length, again few hundreds of ms, and a duty-cycle around 5% or less.

This last phase is not implemented in the GE863-PRO3internal charging algorithm, so that the battery once charged is left discharging down to a certain threshold so that it is cycled from full charge to slight discharge even if the battery charger is always inserted. This guarantees that anyway the remaining charge in the battery is a good percentage and that the battery is not damaged by keeping it always fully charged (Li-Ion rechargeable battery usually deteriorate when kept fully charged).

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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 C2 Vbatt C3 Vrtc DTE GPIO7 / Rftxdisable GSMC11 Simrst C12 Simio D1 Charge D2 VAUX1 D10 GND D11 Simvcc D12 Simclk E1 GND E2 PwrmonPB8 Nrst Reset ARMPB9 ON/OFF*-APPB2 PB0PB1 PB7XIN32 HdmbXOUT32 PA3Reserved GND VBATT2Balls Layout ARM PIO Controller a multiplexing ARM Port IO multiplexingARM PIO Controller B multiplexing ARM PIO Controller C multiplexing Turning on the GE863-PRO3GSM/GPRS Engine Hardware Commands+1,8/5 10kHardware shutdown Hardware Unconditional Reboot of GSM/GPRS Engine2Turning OFF the GE863-PRO3GSM/GPRS Engine Turning ON/OFF the GE863-PRO3ARM ON/OFF*-AP # GND GSM Power Supply Requirements Power SupplyAT+CFUN=1 AT+CFUN=4Vrtc Backup supply ARM Power Supply RequirementsElectrical design Guidelines General Design RulesSuggested circuit is 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 GSM Antenna Requirements Antenna50 ohm GSM Antenna PCB line GuidelinesElectro Magnetic Interference Guidelines GSM Antenna installation GuidelinesOperating Range Interface levels Cmos Level Min Max Logic level specificationsAbsolute Maximum Ratings -Not Functional Parameter Min Max Cmos 3.1V Current characteristics Level Typical GSM Gpio Current characteristics Level TypicalCmos 1.8V-A Current characteristics Level Typical Operating Range Interface levels Cmos Vrtc Level Min MaxSignal Min Max Signal FunctionPhone reset Modem Serial Port Modem Serial Port 2 Debug Serial PortsSignals 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 Short description Input Lines MicrophoneMicmt 1st differential microphone path Input Lines CharacteristicsOutput Lines Speaker Earmt Differential Line-out Drivers Path Output Lines CharacteristicsEvaluation Kit for Telit GE863- PRO3 Modules ON/OFF 10 GSM/GPRS General Purpose I/OUsing a Gpio Pad as Output Using a Gpio Pad as InputUsing the RF Transmission Control GPIO7 10.4Using the Rftxmon Output GPIO3Using the Buzzer Output GPIO4 Using the Alarm OutputDevice Status 10.7Indication of network service availabilityLED status RTC Bypass out 10.9VAUX1 power outputOperating Range VAUX1 power supply 11.1General Mounting the GE863-PRO3on the Application BoardStencil PCB pad DesignSolder paste Following is the recommended solder reflow profile 11.1.4 GE863-PRO3Solder Reflow3C/second max Section A-A Packing SystemModules orientation on tray Moisture Sensibility Conformity Assessment Issues Safety Recommandations Revision Date Changes Document Change Log

1vv0300773a specifications

Telit Wireless Solutions 1VV0300773A is an advanced cellular module specifically designed for a wide range of IoT applications. This module is part of Telit’s extensive portfolio, which is renowned for its reliability and innovation in the wireless communication space. The 1VV0300773A module stands out due to its compact design and robust performance, making it an ideal choice for developers looking to integrate cellular connectivity into their projects.

One of the main features of the 1VV0300773A is its support for multiple communication protocols, which enhances its versatility. The module is designed to support various LTE CAT M1 and NB-IoT networks. These technologies are critical for low-power wide-area network (LPWAN) applications, allowing devices to stay connected over long distances while consuming minimal energy. This is particularly beneficial for battery-operated devices in sectors like smart agriculture, smart cities, and industrial IoT.

The module is equipped with a powerful ARM Cortex-M3 processor, which enables efficient data processing and facilitates complex computations required for many IoT applications. Additionally, it features a comprehensive set of interfaces, including UART, GPIO, and I2C, enabling easy integration with various sensors and peripherals. This modularity ensures that developers can customize their applications based on specific business needs.

Security is another crucial aspect of the 1VV0300773A module. Telit incorporates advanced security features including secure boot, data encryption, and a secure element, ensuring that data transmitted over cellular networks is protected against unauthorized access. This commitment to security is vital in today’s increasingly connected world, where data privacy is a top concern.

Furthermore, the 1VV0300773A module supports extensive over-the-air firmware updates, allowing manufacturers to deploy updates and enhancements seamlessly. This capability extends the lifecycle of devices in the field and ensures that they can adapt to new requirements and security standards over time.

In summary, Telit Wireless Solutions 1VV0300773A offers a blend of advanced features, robust technologies, and essential characteristics tailored for the rapidly evolving IoT landscape. Its combination of multi-network support, secure communication, and efficient processing makes it a standout choice for developers and enterprises looking to enhance their connectivity solutions.
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