Nisshinbo Micro Devices Inc. RP401K181A-TR

RP401x Series are high efficiency, step-up DC/DC converter ICs packaged in compact 5pin SOT23-5 or 6pin DFN(PLP)1820-6. This IC can start up from low voltage (Typ.0.6V), therefore, it is suitable for using with single or 2 serial alkaline batteries, or a nickel-metal-hydride (NiMH) battery, or one-cell Lithium-ion (Li+) battery. This IC consists of an oscillator, a reference voltage unit with soft start, a chip enable circuit, an error amplifier, phase compensation circuits, a slope circuit, a PWM control circuit, a start-up circuit, a PWM/VFM mode control circuit, internal switches and a protection circuit. A low ripple high efficiency step-up DC/DC converter can be composed of the RP401x with only an inductor, a diode, (resisters for adjustable type), and capacitors. The output voltage of the RP401K001s is adjustable, and others are fixed internally. The output voltage range is from 1.8V to 5.5V. RP401Kxx1A/B series have a MODE pin to alternate between PWM fix and PWM/VFM automatic shift to improve the efficiency at light load. If MODE pin is set "H", the mode is PWM fix, and when the MODE pin is set "L", PWM/VFM automatic shift. The RP401xxx1C and D do not have MODE pin. The RP401xxx1C is PWM/PFM alternative type, and the RP401xxx1D is PWM fixed type.

• Low Start-up Voltage guaranteed ··· ··· Typ. 0.6V
• Input Voltage Range ···· ··· 0.6V ~ 5.5V
• High Efficiency ···· ·· 86% (100mA / 3.3V, VIN=1.5V , 25°C )
• Output current ···· ·· 500mA / 1.8V ( VIN=1.5V ) / 5.0V (VIN=3.3V )
• Built-in Lx switch ···· ··· NMOS: 0.4Ω (VOUT = 3.3V, 25°C )
• PWM Oscillator Frequency ···· ···· 1.2MHz
• Output Voltage Range ···· ·· Fixed type: 1.8V to 5.5V with 0.1V Stepwise Adjustable: 1.8V~5.5V (Recommendation range of output voltage)
• Lx peak current limit function ·· ·· Typ. 1.0A
• Latch protection delay time ··· ·· 3.3ms (Only applied to A version)
• Small Packages ···· ·· DFN(PLP)1820-6, SOT23-5

• MP3 players
• PDA
• cellular phones
• Digital Still Cameras
• LCD Bias Supplies
• Portable blood pressure meter
• Wireless Handset
• GPS