Ricoh R5220X Manuals

R5220x SERIES PWM Step-down DC/DC Converter with switch function

The R5220x Series 400mA ∗PWM Step-down DC/DC Converter with Switch Function is a CMOS-based PWM step-down DC/DC converter with synchronous rectifier. R5220x also has the function of switching to the LDO regulator. By switching with the MODE pin, the device can be used as an LDO regulator (Output Current 50mA) in the smaller output current range, while it can be used as a DC/DC converter (Output Current 400mA∗) under high load conditions. (The polarity of the MODE pin is selectable.) The DC/DC converter contains an under-voltage lockout circuit (UVLO), a soft start circuit, and a latch type protection circuit. By simply using an inductor and a capacitor, a high-efficiency DC/DC converter can be easily configured.