AP64351Q Synchronous Buck Converter Diodes Inc. AP64351Q Synchronous Buck Converter is an automotive-compliant, 3.5A, synchronous buck converter with a wide input voltage range of 3.8V to 40V. The device fully integrates a 75mΩ high-side power MOSFET and a 45mΩ low-side power MOSFET to provide high-efficiency step-down DC-DC conversion. Diodes Inc. AP64351Q is easy to use by minimizing the external component count due to its adoption of peak current mode control.