RP509N001D033-EV 1A PWM/VFM Step-down DC/DC Converter with Synchronous Rectifier Evaluation Board No. EEV-362-N001D033-200220 RP509N001D033-EV is the evaluation board for RP509 which has the below features, benefits and specifications. OUTLINE The RP509N is a low supply current PWM/VFM step-down DC/DC converter with synchronous rectifier (1) featuring 0.5 A/1 A output current . Internally, a single converter consists of a reference voltage unit, an error amplifier, a switching control circuit, a mode control circuit, a soft-start circuit, an undervoltage lockout (UVLO) circuit, a thermal shutdown circuit, and switching transistors. The RP509N is employing synchronous rectification for improving the efficiency of rectification by replacing diodes with built-in switching transistors. Using synchronous rectification not only increases circuit performance but also allows a design to reduce parts count. Output voltage controlling method is selectable between a PWM/VFM auto-switching control type and a forced PWM control type, which further reduces noise than a normal PWM control under a light load, and these types can be set by the MODE pin. Output voltage type is selectable between an internally fixed output voltage type and an externally adjustable output voltage type. Protection circuits in the RP509N is current limit circuit and thermal shutdown circuit. LX current limit value (Typ.) is selectable between 1.6 A and 1.0 A. FEATURES Input Voltage Range (Maximum Rating) 2.3 V to 5.5 V (6.5 V) Output Voltage Range (Fixed Output Voltage Type) 0.6 V to 3.3 V, settable in 0.1 V steps (Adjustable Output Voltage Type) 0.6 V to 5.5 V (2) Output Voltage Accuracy (Fixed Output Voltage Type) 1.5% (V 1.2 V), 18 mV (V < 1.2 V) SET SET Feedback Voltage Accuracy (Adjustable Output Voltage Type) 9 mV (V = 0.6 V) FB Output Voltage/Feedback Voltage Temperature Coefficient 100 ppm/C Selectable Oscillator Frequency Typ. 6.0 MHz Oscillator Maximum Duty Min. 100% Built-in Driver ON Resistance (V = 3.6 V) Typ. Pch. 0.195 , Nch. 0.175 (RP509N) IN Standby Current Typ. 0 A UVLO Detector Threshold Typ. 2.0 V Soft-start Time Typ. 0.15 ms Inductor Current Limit Circuit Typ. 1.6 A/1.0 A, selectable Current Limit Package SOT-23-6 ( 2.9 mm x 2.8 mm x 1.1 mm ) (1) This is an approximate value. The output current is dependent on conditions and external components. (2) VSET = Set Output Voltage 1 RP509N No. EEV-362-N001D033-200220 For more details on RP509 IC, please refer to