The TPS51125 is a cost effective, dual-synchronous buck controller targeted for notebook system power supply solutions. It provides 5-V and 3.3-V LDOs and requires few external components. The 270-kHz VCLK output can be used to drive an external charge pump, generating gate drive voltage for the load switches without reducing the main converter's efficiency. The TPS51125 supports high efficiency, fast transient response and provides a combined power-good signal. Out-of-AudioTM mode light-load operation enables low acoustic noise at much higher efficiency than conventional forced PWM operation. Adaptive on-time D-CAPTM control provides convenient and efficient operation. The part operates with supply input voltages ranging from 5.5 V to 28 V and supports output voltages from 2 V to 5.5 V. The TPS51125 is available in a 24-pin QFN package and is specified from -40C to 85C ambient temperature range.