2-MHz Synchronous DC-DC Converters Are Very Efficient

The MAX15038 and MAX15039 are small, synchronous dc-dc converters with outputs up to 4 A and 6 A, respectively. Operating from a 500-kHz to 2-MHz switching frequency, the converters enable the implementation of compact, all-ceramic-capacitor designs. User-selectable, fixed-frequency PWM, and pulse-skipping modes ensure high efficiency during light loads, while integrated low-resistance MOSFETs maximize conversion efficiency at heavy loads. Conversion efficiency is 94% at 1 MHz. The devices integrate a high-bandwidth (28-MHz) voltage-error amplifier, which can be combined with a voltage-mode control architecture to enable the implementation of type III compensation. This topology maximizes bandwidth, improves transient response, and minimizes output capacitance, thus allowing an all-ceramic-capacitor design. Supply voltage is from 2.9 to 5.5 V, and output voltage accuracy over line, load, and temperature variations is ±1%. The MAX15038 and MAX15039 come in a space-saving, 4- by 4-mm TQFN package, and are fully specified over the ?40°C to 85°C extended temperature range. Prices start at $2.73 in quantities of 1000 and up. MAXIM INTEGRATED PRODUCTS, Sunnyvale, CA. (800) 998-8800.