The history of modern day batteries began over two centuries ago when Alessandro Volta invented the first voltaic pile. Since then the batteries have become a common power source for industrial and consumer applications. We usually find them in portable media devices. Some of these batteries are rechargeable and require modern and intelligent electronic circuits for their charge and discharge management.

Managing the batteries results in better energy efficiency and longer life. Battery charger designs have advanced quickly over the last decade. New battery types with different chemistries have been created. These new chemistries required special charging profiles that were not available with conventional battery chargers. Previous complex power-management systems were developed using high-speed analog pulse-width modulation (PWM) circuits combined with digital logic and specialty analog-only circuits.

They were application specific off-the-shelf solutions available for most applications. They had neither the features nor the flexibility to meet specialized requirements. Modern power-management applications have advanced from simple current and voltage regulators towards mixed signal applications utilizing programmable microcontrollers. The combination of a programmable microcontroller and high-speed PWM allows a designer the benefits of programmability and customization.

The microcontroller can adjust the output current, voltage, switching frequency, duty cycle, soft start, and handle system faults when external conditions warrant a change. Programmable battery chargers have the ability to charge different battery pack chemistries without changing any of the circuit hardware. Firmware is used to handle the differences between the battery chemistries and their respective charge profiles.

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