R1223N152F

R1223N SERIES PWM/VFM step-down DC/DC Controller NO.EA-065-130424 OUTLINE The R1223N Series are CMOS-based PWM step-down DC/DC Converter controllers with low supply current. Each of these ICs consists of an oscillator, a PWM control circuit, a reference voltage unit, an error amplifier, a soft-start circuit, a protection circuit, a PWM/VFM alternative circuit, a chip enable circuit, and resistors for voltage detection. A low ripple, high efficiency step-down DC/DC converter can be easily composed of this IC with only four external components, or a power-transistor, an inductor, a diode and a capacitor. With a PWM/VFM alternative circuit, when the load current is small, the operation is automatically switching into the VFM oscillator from PWM oscillator, therefore the efficiency at small load current is improved. The R1223NxxxB type, which is without a PWM/VFM alternative circuit, is also available. If the term of maximum duty cycle keeps on a certain time, the embedded protection ci...