20V synchronous buck controller
1 min read
A synchronous voltage mode buck controller from National Semiconductor can drive a range of high current point of load applications in printers, telecom, networking and embedded computing.
The LM27402 is described as the industry's most feature rich 20V synchronous buck controller and the first to integrate advanced features into one chip.
An input voltage range of 3V to 20V allows the LM27402 to interface with most intermediate bus voltages, including 3.3V, 5V and 12V rails. Integrated inductor dc resistance current sense eliminates the need for resistive power train elements to detect output current. This increases overall power conversion efficiency and allows accurate continuous current limit sensing. Current sense threshold level is programmable to accommodate a range of load current levels.
Output voltage is adjustable down to 0.6V with a 1% voltage reference providing output voltage set point accuracy over temperatures ranging from -40 to 125°C. An integrated bias supply sub regulator eliminates the external bias voltage supply to simplify pcb layout. Integrated high current mosfet gate drivers with adaptive dead time control enable efficient power conversion with load currents as high as 30A. Other features include programmable soft start, tracking and prebiased startup.
Packaging options are 16pin tssop and 4 x 4 mm LLP.
