RP501K Series

1A Step-down DC/DC Converters with synchronous rectifier

Data Sheet / Flyer
Data Sheet * Flyer

The RP501K Series are CMOS-based step-down DC/DC Converters with synchronous rectifier.

Each of these ICs consists of an oscillator, a switching control circuit, a reference voltage unit, an error amplifier, a soft-start circuit, protection circuits, UVLO circuit, switching transistors. A low ripple, high efficiency step-down DC/DC converter can be easily composed of this IC with only an inductor and capacitors. In terms of the output voltage, since the feedback resistances are built-in, the voltage is fixed internally. 50mV (custom-made) step output can be set by laser-trim and ±1.5% or ±24mV tolerance depending on the output voltage is guaranteed.

Mode alternative circuit works automatically for improving the efficiency. Considering fixed noise frequency, PWM fixed control type is also available. As protection circuits, the current limit circuit which limits peak current of LX at each clock cycle, and the latch type protection circuit which works if the term of the over-current condition keeps on a certain time exist. The latch-type protection circuit works to latch an internal driver with keeping it disable. To release the condition of the protection, after disabling this IC with a chip enable circuit, enable it again, or restart this IC with power-on or make the supply voltage at UVLO detector threshold level or lower than UVLO.

Since the package is DFN(PLP)2527-10, high density mounting on boards is possible.

Input Voltage Range 2.5V to 5.5V
Output Voltage 1.0V to 3.3V
High Accuracy Output Voltage ±1.5% (Vout>=1.6V)
±24mV (Vout<1.6V)
Oscillator Frequency Typ. 2.25MHz
Built-in Soft start Function Max. 0.2ms
Built-in Peak current limit Typ. 1.5A
Built-in UVLO Function Typ. 2.2V
Switching Mode can be controlled by Mode pin Automatic PWM/VFM mode change / PWM fixed
Package DFN(PLP)2527-10

  • Power source for portable equipment such as cellular, PDA, DSC, Notebook PC
  • Power source for HDD, WLAN, Car accessories
  • Power source for Li-ion battery-used equipment

Data Sheet Flyer Design Guide
RP501K Series (1.17MB) RP501K Series RP501Kxx1x Series
Package Info. Mark Info. Quality Assurance Data
DFN(PLP)2527-10 RP501K Reliability

All PDF files are less than 1MB unless otherwise stated.

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