Step-Up Converter Extends Battery Life

Targeting portable designs, the ST5Rxx family of dc-to-dc step-up converters offers a wide range of output voltages, up 100 mA of output current, and low ripple and noise. Using only three external components--a diode, capacitor and inductor--the devices accept any positive dc voltage as low as 0.9V and convert it to 2.5V, 2.8V, 3.0V, 3.3V, or 5V, accurate to within ±2.5% at 25°C.Using voltage-to-frequency modulation, current draw is 16 µA at no load with an input voltage of 2.4V. The devices have an efficiency of 85%, typical, and frequency at full load is set at 150 kHz by an internal oscillator. The ST5Rxx family is available now.