New Industry Products

Fairchild’s Eco-Friendly Battery Charger Reduces Charge Time and Powers USB Peripherals

April 16, 2013 by Jeff Shepard

Today's mobile devices are becoming powerful computing products, with an increasingly feature-rich, immersive user experience. With the emergence of USB charging standards and the continuing trend for electronic devices, especially handsets, to be powered through the USB port, product designers are faced with the challenge of enabling advanced product features while quickly and safely charging high-capacity batteries and supporting connected peripherals. Fairchild Semiconductor's FAN54015 USB-compliant single-cell Li-ion switching charger provides designers a balance of safety, accuracy, efficiency, and solution size for charging mobile device batteries.

To reduce charge time and mitigate heat dissipation, the FAN54015 switching charger employs a high-efficiency, eco-friendly, 3MHz DC-DC synchronous buck converter capable of supplying 1.45A. Additionally, to accommodate legacy and emerging lithium battery technologies, the regulated battery float voltage can be programmed from 3.5V to 4.44V. The device’s innovative system architecture allows reverse use of the switch-mode buck converter, resulting in a 500mA USB on-the-go (OTG) boost regulator, and providing power for USB peripherals.

To protect the battery and maximize mobile device usage time, the FAN54015 device supports battery charging in three phases: pre-conditioning, constant current (CC), and constant voltage (CV). An integrated over-voltage protection (OVP) FET blocks current flow when the input voltage reaches dangerous levels, eliminating the need for an external protection MOSFET and thereby reducing complexity and bill of material (BOM) costs.

The FAN54015 charger is fully programmable via an I2C interface, allowing setup of custom charging profiles and is part of a growing family of battery charging solutions that combine safety, accuracy, and fast charging time, while reducing overall solution cost.

Features and benefits of the FAN54015 charger includes: Fast charging for single cell lithium battery with 1.45A current; Cooler and safer device charging with greater than 95 percent efficiency; Longer battery life with lowest quiescent current and greater than 94 percent efficiency in USB-OTG; Input and battery over-voltage protection and thermal regulation; Programmability of input and output power and OTG boost regulator; 0.5 percent voltage regulation and 3.0 percent charge current accuracy ensures complete charge of the battery; 1.96mm x 1.87mm footprint, 20-bump WL-CSP package with minimal external components; and pulse width modulated (PWM), 3MHz, synchronous buck converter enables use of a tiny 1µH inductor.

In lots of 1,000 pieces, the FAN54015 costs US $1.27. Samples are available upon request with production quantities available 8-12 weeks ARO.