AN1146 - Application Circuit based on AP3420 2A Step-Down DC-DC Converter

Application circuit for AP3420 is a 2A step-down DC-DC converter. At heavy load, the constant frequency PWM control performs excellent stability and transient response. No external compensation components are required. The AP3420 supports a range of input voltages from 2.7 to 5.5V, allowing the use of a single Li+/Li- polymer cell, multiple Alkaline/NiMH cell, and other standard power sources. The output voltage is adjustable from 0.6V to the input voltage. The AP3420 employs internal power switch and synchronous rectifier to minimize external part count and realize high efficiency