RP506K series 2A PWM/VFM step-down DC/DC converter with synchronous rectifier. RP506K can be selected from two control types by input signal to the MODE pin - forced PWM control or PWM/VFM auto switching control in which mode automatically switches to high-efficiency VFM mode in low output current. The xx1A/B/D/E version with an internally fixed output voltage type and the 001C/F version with an externally adjustable output voltage type are available. RP506K includes a soft start circuit, an under-voltage lockout circuit (UVLO), thermal shutdown circuit and a latch protection circuit. By simply using an inductor, (resistors) and capacitors as external components, a high-efficiency step-down DC/DC converter can be easily configured. The oscillator frequency can be selected from 1.2MHz or 2.25MHz.The soft start time is Typ. 0.15ms, and by connecting an external capacitor to TSS pin, soft start time is adjustable. VOUT/VFB pin voltage is monitored, and the output voltage errors can be output from PG pin. The PG pin is N-channel open drain output type. The DFN(PLP)2527-10 package is available.