“The project presented here is a powerful constant-frequency, pulse-width modulating (PWM), current-mode step-up DC-DC switching regulator efficiently producing 5V from input voltages between 3V to 5V. The project can be used in a portable device that works with a battery. The module produces a peak current of up to 1A and an output voltage of 5V DC.
The MAX668 current-mode PWM controllers operate in a wide range of DC-DC conversion applications, including boost, SEPIC, flyback, and isolated output configurations. Optimum conversion efficiency is maintained over a wide range of loads by employing both PWM operation and Maxim’s proprietary Idle Mode control to minimize operating current at light loads. Other features include shutdown, adjustable internal operating frequency or synchronization to an external clock, soft start, adjustable current limit, and a wide (1.8V to 28V) input range.”