Intersil 2.5A Buck Regulator Operates During Cold Crank Conditions

Intersil Corp. has released a new 2.5A step-down regulator that automatically boosts the input voltage to maintain regulation.

Loss of regulation due to drooping input voltage is a common problem in automotive applications. Such input dropouts – commonly called ’cold crank’ conditions – occur when starting a car in cold conditions, but can now occur in vehicles with start-stop operation.

The ISL78200 is a synchronous buck/pre-boost IC that automatically activates a pre-boost stage when required to maintain output regulation. It integrates a low side MOSFET driver along with a 90mΩ high side MOSFET. The ISL78200 can accommodate a wide input voltage range of 3 to 40V while supplying a regulated 5V, 2.5A output at 85°C without heat sinking. The combination of input voltage pre-boosting and step-down regulation with a low 180µA quiescent current makes the ISL78200 ideal for a wide range of automotive power applications.

Also available now from Intersil is the ISL78205, a similar regulator that does not provide pre-boost capabilities. Like the ISL78200, it is designed for full 2.5A output at 85°C, and can be used for general purpose power regulation and 24V bus power applications. Both devices are AEC-Q100 qualified and TS16949 certified.

The ISL78200 and ISL78205 are available in 20-pin HTSSOP packages with pricing at $0.98 and $0.88 each, respectively, in 50,000-unit quantities.