DC/DC Converters Extend Battery Life
Maxim Integrated Products MXIM) has introduced the MAX8581/MAX8582 high-efficiency, step-down DC/DC converters that can continuously deliver 600 mA. Available in a 9mm2 package, these devices integrate a 65 mΩ bypass FET. During high-power transmission, this bypass FET connects the power amplifier (PA) directly to the battery with a dropout of 33 mV at 500 mA, thus minimizing power loss at the inductor and allowing minimal battery voltage for device usage. To maximize PA efficiency, the output can be varied from 0.4 V to Vin, depending on the distance to the base station and the desired transmission mode (voice or data).