The TS3405 makes simple work out of implementing a complete control and protection scheme for a DC-DC step-down converter. Designed to drive N-channel MOSFETs in a synchronous buck topology, the TS3405 integrates the control, output a adjustment, monitoring and protection functions. The TS3405 provides simple, single feedback loop, voltage mode control with fast transient response. The output voltage can be precisely regulated to as low as 0.8V, with a maximum tolerance of 1.5% over temperature and line voltage variations. A fixed frequency oscillator reduces design complexity, while balancing typical application cost and efficiency. The error amplifier features a 15MHz gain-bandwidth product and 8V/uS slew rate, which enables high converter bandwidth for fast transient performance. The resulting PWM duty cycles range from 0% to 100%. The protection from over current conditions is provided by monitoring the Rds(on) of the lower MOSFET to inhibit PWM operation appropriately. This approach simplifies the implementation and improves efficiency by eliminating the need for a current sense resistor.