RP401x Series


Data Sheet / Flyer
Data Sheet * Flyer

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)
Output current TYP. 500mA/1.8V,VIN=1.5V
TYP. 500mA/5.0V,VIN=3.3V
Built-in Lx switch  TYP. 0.4Ω (VOUT=3.3V)
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,SOT-23-5
  • MP3 players, PDA, cellular phones
  • Digital Still Cameras
  • LCD Bias Supplies
  • Portable blood pressure meter
  • Wireless Handset
  • GPS
Data Sheet Flyer Design Guide
RP401x Series RP401x Series RP401x Series
Package Info. Mark Info. Quality Assurance Data
DFN(PLP)1820-6 RP401K Reliability
SOT-23-5 RP401N Reliability

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