Regulators offer 96% efficiency for battery-powered systems

In hand-held device applications where the input voltage may be higher or lower than the output voltage, buck-boost regulators improve efficiency and provide longer battery life compared to a boost regulator plus bypass solution. With increasing demands for smaller and smaller footprints, Intersil’s ISL9112x compact QFN and WLCSP packages enable power designs that maximise efficiency while providing flexibility and ease of design.

The ISL91127 and ISL91128 operate in buck, boost or buck-boost mode, depending on the relation between input and output voltages and provide smooth transitions between modes to prevent noise and glitches. This capability, combined with patented Intersil technology for delivering superior light load efficiency with ultra-low quiescent current, maximises efficiency under all conditions. This is essential to improve battery life by reducing power drain and heat dissipation in portable and mobile applications.

The buck-boost regulators’ wide input voltage range of 1.8 to 5.5V supports multiple battery topologies, and their wide output voltage range of 1 to 5.2V combined with 3A output current provide the ultimate in design flexibility. The ISL91128 also features I2C programmable dynamic output voltage adjustability, which eliminates feedback resistors and allows the reuse of the same design for multiple output voltage needs.

Andy Cowell, Senior Vice President, Mobile Power Products, Intersil, commented: “Hand-held device designers are constantly challenged to create smaller, more efficient products whether it is the latest wearable, a portable medical device or next-gen smartphone. Intersil specialises in providing the most efficient power delivery with excellent transient response. Our latest buck-boost regulators leverage generations of experience in the most demanding mobile applications to provide customers with extended battery life in a compact, easy-to-use package.”

The ISL91127 and ISL91128 can be combined with the ISL9003A, ISL9016, ISL9021A and ISL9001A LDOs to support multiple output rails with improved ripple. They also work with the ISL9113 sync boost converter and ISL91133 boost regulator if additional higher voltage rails are required, and lower voltage rails are supported with the ISL9104 and ISL9103 sync buck converters.

The ISL91127IR is available now in a 4x4mm, 20-pin QFN package and is priced at $1.29 in 1,000 unit quantities. The ISL91127 is also available in a 20-bump, 2.15x1.74mm WLCSP package priced at $1.25. The ISL91128 is available now in a 20-bump, 2.15x1.74mm WLCSP priced at $1.25 in 1,000 unit quantities. The ISL91127IRN-EVZ fixed 3.3V evaluation board and ISL91127IRA-EVZ adjustable voltage evaluation board are available for purchase.