RT5721 Datasheet | Richtek

2.4MHz 1A Step-Down Converter with I2C Interface General Description The RT5721 is a step-down switching voltage regulator that delivers a digitally programmable output from an input voltage supply of 2.5V to 5.5V. The output voltage is programmed through an I2C interface capable of operating up to 3.4MHz. Using a proprietary architecture with synchronous rectification, the RT5721 is capable of delivering 1A continuously at over 80% efficiency, maintaining that efficiency at load currents as low as 10m A. The regulator operates at a nominal fixed frequency of 2.4MHz, which reduces the value of the external ponents. Additional output capacitance can be added to improve regulation during load transients without affecting stability. At moderate and light loads, Pulse Frequency Modulation (PFM) is used to operate in Power-Save Mode with a typical quiescent current of 45A at room temperature. Even with such a low quiescent current, the part exhibits excellent transient response during large load swings. At higher loads, the system automatically switches to fixed- frequency control, operating at 2.4MHz. In the Shutdown Mode, the supply current drops below 1A, reducing power consumption. The PFM Mode can be disabled if fixed frequency is desired. The RT5721 is available in a small WL-CSP11B 1.31x1.62 (BSC). Features - Steady 2.4MHz Switching Frequency - Fast Load Transient - Continuous Output Current Capability: 1A - 2.5V to 5.5V Input Voltage Range - Digitally Programmable Output Voltage - 0.3V to 1.3V Programmable Slew Rate for Voltage Transitions - I2C-patible Interface Up to 3.4MHz - PFM Mode for High Efficiency in Light Load - Quiescent Current in PFM Mode: 45A (Typical) - Input Undervoltage Lockout (UVLO) - Thermal Shutdown and Overload Protection - Power Good Indicator Applications - Application, Graphic, and DSP Processors - ARMTM, Tegra TM, OMAPTM, Nova Thor TM, ARMADATM, Krait TM, etc. - Hard Disk Drives, LPDDR3, LPDDR4 - Tablets, Netbooks,...