RP503Z (WLCSP-6-P2) is the discontinued product. As of June in 2016. RP503x SERIES 600mA Step-down DC/DC Converter with Synchronous Rectifier NO.EA-235-140530 OUTLINE The RP503x Series are low supply current CMOS-based 600mA step-down DC/DC Converters with synchronous rectifier. Each of these ICs consists of an oscillator, a switching control circuit, a reference voltage unit, an error amplifier, a soft-start circuit, UVLO circuit, a latch protection circuit, switching transistors, and so on. A low ripple, high efficiency step-down DC/DC converter can be easily composed of this IC with only an inductor and capacitors. In terms of the output voltage, since the feedback resistances are built-in, the voltage is fixed internally. 0.1V step output can be set by laser-trim and 1.5% or 18mV tolerance depending on the output voltage is guaranteed. RP503x is PWM/VFM auto switching control in which mode automatically switches from PWM mode to high-efficiency VFM mode in low output current. The efficiency in low output current (VFM mode) improved compared with existing products. As protection circuits, the current limit circuit which limits peak current of Lx at each clock cycle, and the latch type protection circuit which works if the term of the over-current condition keeps on a certain time exist. The latch-type protection circuit works to latch an internal driver with keeping it disable. To release the condition of the protection, after disabling this IC with a chip enable circuit, enable it again, or restart this IC with power-on or make the supply voltage at UVLO detector threshold level or lower than UVLO. Since packages are WLCSP-6-P2, DFN1616-6, SOT-23-5, high density mounting on boards is possible. )This is an approximate value, because output current depends on conditions and external parts. FEATURES Supply Current ......................................................Typ. 20A (at VFM mode, at no load) Standby Current ....................................................Max. 5A Input Voltage Range .............................................2.5V to 5.5V (Absolute maximum rating 6.5V) Output Voltage Range...........................................0.8V to 2.5V (0.1V step) Output Voltage Accuracy.......................................1.5% (VOUT1.2V), 18mV (VOUT<1.2V) Temperature-Drift Coefficient of Output Voltage ...Typ. 100ppm/C Oscillator Frequency.............................................Typ. 2.0MHz Oscillator Maximum Duty Cycle............................Min. 100% Built-in Driver ON Resistance ...............................Typ. Pch. 0.34, Nch. 0.43 (VIN=3.6V) UVLO Detector Threshold.....................................Typ. 2.2V Soft Start Time.......................................................Typ. 0.15ms Lx Current Limit.....................................................Typ. 800mA Latch type Protection Circuit.................................Typ. 1.5ms Two choices of Switching Mode............................Automatic PWM/VFM mode change Packages..............................................................DFN1616-6, WLCSP-6-P2, SOT-23-5 APPLICATIONS Power source for battery-powered equipment. Power source for hand-held communication equipment, cameras, VCRs, camcorders. Power source for HDD, portable equipment. 1 RP503Z (WLCSP-6-P2) is the discontinued product. As of June in 2016. RP503x BLOCK DIAGRAMS RP503Zxx1A RP503Lxx1A VIN Chip Ramp Current CE Enable Compensation Feedback OSC Current LX Protection Vref PWM Switching Control Control Soft Start VOUT UVLO AGND PGND RP503Zxx2A RP503Lxx2A VIN Chip Ramp Current CE Enable Compensation Feedback OSC Current LX Protection Vref PWM Switching Control Control Soft Start VOUT UVLO AGND PGND 2