12 A Synchronous Buck regulator with FAST COT control, adjustable current limit & voltage tracking The TDA38813 is a 12 A fully integrated and highly efficient DC-DC buck regulator. It uses a fast Constant On-Time (COT) control scheme, which simplifies the design efforts and achieves fast transient response while maintaining excellent line and load regulation. It can operate over a wide range of input voltage (2.7 V to 16 V) using an external bias supply.