Intersil targets mobile devices with buck-boost/boost switching regulators

March 21, 2014 // By Graham Prophet
As part of the company’s re-focussing on power management product lines, Intersil has introduced high-integration switching regulators that are designed to obtain the maximum usable life from the typical single-cell lithium-ion battery used in mobile devices.

The ISL911xx switching regulators are high-current buck-boost and boost devices packaged in a tiny, integrated CSP, enabling improved efficiency for high current designs in a small form factor. The ISL911xx switching regulators - ISL91110, ISL91108 and ISL91117 – have an architecture that offers up to 96% efficiency to extend battery life and reduce overheating in high-current handheld devices. The architecture allows for smooth transitions from buck to boost to prevent glitches and noise in smartphones, tablets and other single-cell lithium ion (Li) battery-based systems.

Intersil’s ISL91110 and ISL91108 buck-boost switching regulators are used in mobile devices to supply the system power management IC (PMIC), the Wi-Fi or radio frequency (RF) power amplifier, as well as other system peripherals such as the camera and memory interfaces. The ISL911xx family is based on proprietary, fully synchronous four-switch architecture. This advanced architecture enables the seamless transition from buck to boost, delivery of up to 2.5A output current at the lowest single-cell Li battery voltages to significantly improve power efficiency, increase battery life and prevent overheating of mobile devices. The ISL91117 boost converter is ideal for USB on-the-go implementations in handheld devices that require high current and high efficiency.

Fast transient response is combined with the ability to cover the full range of the most advanced Li battery chemistry. The ISL911xx family was designed with space constrained applications in mind and is capable of working with the smallest inductors and capacitors, making them the ideal converter solution for mobile devices. A 2.6 MHz switching frequency reduces the power supply solution size. The footprint of the device is 2.34 by 1.72 mm, and the switching regulators require only a single inductor and very few external components, minimizing overall space requirements.

• The ISL91110 is the highest-current switching regulator of the series and was designed for smartphone and tablet PC OEMs as a supply for the system PMIC, the Wi-Fi or RF power amplifiers, or other