High Power Synchronous Boost Converter

The RT8540A is a high-efficiency, high-current Boost converter in all single-cell Lithium-ion / polymer battery operated products. The RT8540A maintains output current regulation by switching the internal high side and low side switch transistors. The transistor switches are pulse-width modulated at a fixed frequency of 2MHz. The high switching frequency allows the use of a small inductor and output capacitor, making the RT8540A ideally suited for small battery-powered applications. Output voltage can be set by an external resistor on the FB pin or by I²C interface.

The RT8540A contains over voltage protection, over current protection and over temperature protection to prevent the device from output open circuit or short circuit condition. Built-in soft-start circuitry prevents excessive inrush current during start-up. The shutdown feature reduces quiescent current to less than 5μA.