ISL78200 2.5A Buck Regulator from Intersil Operates During ‘Cold Crank’ Conditions

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 90 milliohm high side MOSFET. The ISL78200 can accommodate a wide input voltage range of 3V to 40V while supplying a regulated 5V, 2.5A output at 85 degrees C without heat sinking. The combination of input voltage pre-boosting and step-down regulation with a low 180uA 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 degrees C, and can be used for general purpose power regulation and 24V bus power applications. Both devices are AEC-Q100 qualified and TS16949 certified. Intersil will feature the ISL78200 and ISL78205 at the annual Battery Show in Novi, Michigan on October 25-27, 2011.

Features and Specifications
• Regulation maintained even with inputs voltages down to 3V (ISL78200)
• Wide 3V to 40V input voltage range
• 2.5A output capability without heat sinking (up to 85C ambient)
• Guaranteed 3.0A cycle-by-cycle current limit
• 180uA quiescent current
• Programmable switching frequency from 200kHz to 2.2MHz with synchronization capability
• Selectable forced-PWM and PFM operating modes
• AEC-Q100 qualified and TS16949 certified

Pricing and Availability
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.