High-Efficiency 3-Level Synchronous Buck Controller

The RAA489301 is a 3-level buck voltage controller that provides seamless transitions among VOUT < VIN/2, VOUT = VIN/2, and VOUT > VIN/2. The RAA489301 offers a wide range of regulated output voltages and high efficiency. It also reduces the inductor size significantly.

The advanced Renesas R3™ Technology provides high light-load efficiency, fast transient response, and seamless DCM/CCM transitions. The RAA489301 supports input sources such as batteries of various chemistries in 2S to 5S configurations. It also supports the USB PD adapter, safely converting it to a regulated output voltage of up to 24V. The RAA489301 can also convert a wide range of input-side DC power sources to a regulated output voltage.

In addition to a 3-level buck configuration, the RAA489301 supports pass-through mode (PTM) in both forward and reverse directions. The PTM allows high efficiency for modes in which the input and output voltage are identical. The RAA489301 has independent control loops for the input voltage, input current, output voltage, and output current so that it can be used as a pre-regulator for a CPU power supply rail system.

The RAA489301 includes system operation functions such as the isolation MOSFET control, adjustable output voltage, programmable switching frequency, and a power-good indicator. The protection functionalities include OCP, OVP, UVP, and OTP. The RAA489301 has serial communication through SMBus/I2C that allows the programming of many critical parameters to deliver a customized solution. These programming parameters include but are not limited to, minimum input voltage, maximum output voltage, maximum input current limit, and maximum output current limit setting.