R1230D181B-TL

PWM/VFM Step-down DC-DC Converter with Synchronous Rectifier

■OUTLINE

 The R1230D Series are PWM step-down DC/DC Converters with synchronous rectifier, low supply current by CMOS process. Each of these ICs consists of an oscillator, a PWM control circuit, a reference voltage unit, an error amplifier, a soft-start circuit, protection circuits, a protection against miss operation under low voltage UVLO, PWM/VFM alternative circuit, a chip enable circuit, and a driver transistor.

■FEATURES

●Built-in Driver ON Resistance • • • • • • • • • • • • •P-channel 0.35Ω, N-channel 0.45Ωat VIN=3V

●Built-in Soft-start Function TYP. 1.5ms, and Latch-type Protection Function Delay Time; TYP. 1.5ms

●Two choices of Oscillator Frequency • • • • • •500kHz, 800kHz

●PWM/VFM alternative with MODE pin • • • • • •PWM operation; MODE pin at “L”,

VFM operation; MODE pin at “H”

●High Efficiency • • • • • • • • • • • • • • • • • •TYP. 90%

●Output Voltage • • • • • • • • •Stepwise Setting with a step of 0.1V in the range of 1.2V ∼4.0VXX1A/B Type

or adjustable in the range of 0.8V to VIN001C/D Type

●High Accuracy Output Voltage • • • • • • • • • •±2.0%XX1A/B Type

●Package • • • • •SON8 Max height 0.9mm, thin type

■APPLICATIONS

●Power source for portable equipment.