Understanding System Loads and Interfacing with Chargers

Focus:

In battery-powered portable products, the use of the battery charger to power the product is aided by the presence of the battery, which can be used to supply peak loads beyond the capacity of the charger. However, there are times when it's desirable to power the product from the charger without the battery present. But to do this requires that designers take measures to ensure that the start-up or transient conditions in the application do not cause the charger to go into a short-circuit protection mode. This article discusses Li-ion charger and system-load characteristics that must be considered and power management design tips for powering the product off of the charger. Although the concepts discussed can be applied to other battery chemistries, much of the discussion focuses on the three phases associated with charging of Li-ion batteries.

What you’ll learn:

• How to design battery-powered products so they can be powered off of the battery charger when the battery is not present
• How to understand potential fault conditions that can arise when a battery-powered product is powered directly from the charger with no battery present

Notes:

Article appears on pages 32-34 of March issue in article archive. You must register to access articles in this magazine's archive.

View the Source

Author & Publication:

Charles Mauney, Senior Battery Charger Applications Engineer, Texas Instruments, Bodo's Power Systems, Mar 01 2009

This article summary appears
in the HOW2POWER Design Guide.

The Design Guide offers
organized access to
hundreds of articles
on dozens of power conversion
and power management topics.

The Design Guide search results
include exclusive summaries
and accurate "how to" analysis
to help you make faster,
more informed decisions.

Search
for more articles