RP500x Series
Step-Down DC/DC CONVERTER with Synchronous Rectifier

Outline

The RP500X 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, and so on. 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 packages are PLP1820-6, SOT23-6, WLCSP-6 (0.16φ), high density mounting on boards is possible.

Features

Output Current

Min. 400mA

Input Voltage Range

.2.55V to 5.50V

Output Voltage

1.1V to 3.3V

High Accuracy Output Voltage

±1.5% (Vout≥1.6V)
±24mV (Vout<1.6V)

Oscillator Frequency

Typ. 1.2MHz/3.3MHz(We changed the product name of 3.3MHz device.)

Built-in Soft-start Function

Typ.0.1ms

Built-in Lx Peak Current Limit

Typ. 900mA

Built-in Latch type Protection

Typ. 1.5ms

Built-in UVLO Function

Typ. 2.2V

Two choices of Switching Mode

Automatic PWM/PFM mode change / PWM fixed

Package

PLP1820-6, SOT23-6W, WLCSP-6 (0.16φ)(Under Development)

Applications

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

Documents Download

Data Sheet (PDF)	Package Info. (PDF)	Mark Info. (PDF)	Quality Assurance Data (PDF)
RP500x Series EA-155-070919(645KB)	PLP1820-6	to be prepared	to be prepared	to be prepared
	SOT-23-6W	to be prepared	to be prepared	to be prepared
	WLCSP-6(0.16f) (Under Development)	to be prepared	to be prepared	to be prepared