Linear Technology Korea (CEO Hong Sa-kwak, www.linear.com ) announced the release of the synchronous buck-boost DC/DC controller (product name: LTC3789), which boasts a very high efficiency of up to 98%. This product operates even if the input voltage is higher, lower, or equal to the regulated output voltage. High-power step-up and step-down circuits typically require two DC/DC converters, including a transformer or one converter for step-up (boost) and one converter for step-down (buck) conversion. The LTC3789 operates as a single inductor with 4-switch synchronous rectification and can provide up to 150W of output power with a single device. Additionally, higher output power can be achieved by connecting multiple circuits in parallel.

The LTC3789 operates at a selectable fixed frequency of 200 kHz to 600 kHz and can be synchronized with an external clock within the same range using its integrated phase-locked loop (PLL). With a wide input range of 4 V to 38 V, an output range of 0.8 V to 38 V, and smooth transitions between operating modes, it is ideal for a wide range of industrial control, automotive, solar, and high-power battery power systems.

The LTC3789 utilizes a proprietary current-mode control architecture for constant-frequency operation in buck or boost modes and includes a powerful onboard quad N-channel MOSFET gate driver. Additionally, it provides precise constant-current regulation loops for input or output current across a wide input voltage range. The input current limiting function prevents input source overload, while the output current limiting provides an easy solution for regulated output current applications such as battery chargers or LED drivers. Fault protection against overvoltage, overcurrent, and short circuit conditions is provided in all operating modes. Additionally, the LTC3789 cuts off the input voltage from the output during shutdown. Users can select continuous or pulse skip modes to maximize light-load efficiency. The LTC3789 features adjustable soft start and power good output, and maintains a reference voltage accuracy of ±1.5% over an operating junction temperature range of -40°C to 125°C.

The LTC3789 is currently available in 28-pin 4mm x 5mm QFN and 28-pin SSOP packages. Pricing starts at $4.65 per unit for orders of 1,000. For more information, please refer to www.linear.com/3789 .