TPS51275

TPS51275, TPS51275B, TPS51275C www.ti.com SLUSB45B – JUNE 2012 – REVISED MARCH 2013 Dual Synchronous, Step-Down Controller with 5-V and 3.3-V LDOs FEATURES 1 APPLICATIONS 2 Input Voltage Range: 5 V to 24 V Notebook Computers Output Voltages: 5 V and 3.3 V (Adjustable Range ±10%) Built-in, 100-mA, 5-V and 3.3-V LDOs Clock Output for Charge-Pump ±1% Reference Accuracy Adaptive On-Time D-CAP™ Mode Control Architecture with 300-kHz and 355-kHz Frequency Setting Auto-skip Light Load Operation (TPS51275, and TPS51275C) OOA Light Load Operation (TPS51275B) Internal 0.8-ms Voltage Servo Soft-Start Low-Side RDS(on) Current Sensing Scheme Built-In Output Discharge Function Separate Enable Input for Switchers Dedicated OC Setting Terminals Power Good Indicator OVP, UVP and OCP Protection Tablet Computers DESCRIPTION The TPS51275, TPS51275B and TPS51275C are cost-effective, dual-synchronous buck controllers targeted for notebook system-power supply solutions. It provides 5-V and 3.3-V LDOs and requires few external components. The 260-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 efficiency. The TPS51275, TPS51275B and TPS51275C supports high efficiency, fast transient response and provides a combined power-good signal. Adaptive on-time, DCAP™ control provides convenient and efficient operation. The device operates with supply input voltage rang...