• 0.3V to 1.85V Programmable Slew Rate for Voltage Transitions
• Steady 2.4MHz Switching Frequency
• Best-in-Class Load Transient
• Continuous Output Current Capability : 3A
• 2.5V to 5.5V Input Voltage Range
• Digitally Programmable Output Voltage
• I2C-Compatible Interface Up to 3.4Mbps
• PFM Mode for High Efficiency in Light Load
• Quiescent Current in PFM Mode : 45μA (Typical)
• Input Under-Voltage Lockout (UVLO)
• Thermal Shutdown and Overload Protection
• 15-Ball WL-CSP Package


• Application, Graphic, and DSP Processors
• ARMTM, TegraTM, OMAPTM, NovaThorTM, ARMADATM, KraitTM, etc.
• Hard Disk Drives, LPDDR3, LPDDR4
• Tablets, Netbooks, Ultra-Mobile PCs
• Smart Phones
• Gaming Devices


The RT5738 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 RT5738 is capable of delivering 3A continuous at over 80% efficiency, maintaining that efficiency at load currents as low as 10mA. The regulator operates at a nominal fixed frequency of 2.4MHz, which reduces the value of the external components. 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 40μA 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 fixedfrequency control, operating at 2.4MHz. In Shutdown Mode, the supply current is typically 0.1μA, excellent in reducing power consumption. PFM Mode can be disabled if fixed frequency is desired. The RT5738 is available in a
small WL-CSP-15B 1.31x2.02 (BSC)