DC/DC Regulator Controller Sports Ultra-Wide Voltage Range May 20, 2008
Dubbed the industry’s first emulated current-mode-controlled buck-boost DC/DC regulator controller with a best-in-class operating voltage range from 3V to 75V, the LM5118 features a programmable switching frequency up to 500 kHz and a peak efficiency of 95%. Integrating all necessary functions to implement a buck-boost regulator using a minimum of external components, the device's buck-boost topology maintains output voltage regulation when the input voltage is either less than or greater than the output. It operates as a buck regulator when the input voltage is sufficiently greater than the regulated output and gradually transitions to buck-boost mode as the input voltage approaches the output. Reportedly, the dual-mode approach maintains regulation over a wide range of input voltages with optimal conversion efficiency in the buck mode and a glitch-free output during mode transitions. Other features include drivers for the high side buck MOSFET and the low-side boost MOSFET. Available in a 20-pin TSSOP, price is $2.92 each/1,000. NATIONAL SEMICONDUCTOR CORP., Santa Clara, CA. (800) 272-9959.
