Intersil announced two new 55 V two-phase synchronous boost controllers with integrated high-side and low-side MOSFET drivers. The ISL78227 and ISL78229 simplify the design of high-power automotive applications. Operating from a 12 V battery supply, these devices boost the output voltage to 24 V, 36 V or 48 V for 200 W to 800 W trunk audio amplifiers, start-stop systems, and headlamp LED strings. Both controllers also address the rigorous demands of industrial and telecom applications.

The ISL78227 and ISL78229 support wide input and output ranges of 5 V to 55 V and deliver greater than 95 % efficiency. The ability to interleave two controllers for a four-phase application effectively doubles the output power and reduces input/output ripple, allowing power supply designers to use smaller capacitors. Protection features keep the ISL78227 and ISL78229 operating under virtually any condition. Their soft-on function ensures smooth transition from discontinuous-conduction mode (DCM) to continuous-conduction mode (CCM) after completing a soft-start, keeping the power supply safe under all start-up conditions.

The ISL78227 and ISL78229 also offer an envelope-tracking feature that dynamically adjusts or scales the output voltage on the fly to meet system load demands. For example, when the battery supply is low, power consumption of various components such as the audio amplifier must be limited, especially if the radio is on while the engine is off. Transient events such as the start-stop system restarting the engine also require on-the-fly voltage adjustments. And to simplify the task of attaining the ISO 26262 automotive safety integrity level (ASIL) rating, the ISL78229 offers a digital PMBus™ interface for control, telemetry and diagnostics. A video explains the ISL78227/29 solution. “Applications such as Start/Stop are recognized as mild-hybrid and require a 48 V supply, independent from the actual oil price of today's $35 per barrel”, comments Automotive Marketing Manager Edward J. Kohler.

Intersil's PowerNavigator software simplifies the ISL78229's PMBus configuration, validation, monitoring, and telemetry. The tool makes it easy to change features and functions of a digital power supply design without writing a single line of code. To download the PowerNavigator GUI and watch a tutorial video, please visit: www.intersil.com/powernavigator

The ISL78227 55 V synchronous boost controller is available now in a 5 mm x 5 mm, 32-lead WFQFN package and is priced at $3.45 in 1k quantities. An ISL78227EV1Z evaluation board can be purchased for $127. More information www.intersil.com/products/isl78227. The ISL78229 55 V synchronous boost controller with PMBus is available now in a 6 mm x 6 mm, 40-lead WFQFN package and is priced at $3.95 in 1k quantities. An ISL78229EV1Z evaluation board can be purchased for $172 each. More information ww.intersil.com/products/isl78229