*R1203L(DFN1616-6B) is the non-promotional product of as February 2021. R1203x SERIES STEP-UP DC/DC CONVERTER FOR WHITE LED BACK LIGHT NO.EA-271-180703 OUTLINE The R1203x Series are PWM control type step-up DC/DC converter ICs with low supply current. The R1203x is fully dedicated to drive White LEDs with constant current. Each of these ICs consists of an NMOS FET, an oscillator, a PWM comparator, a voltage reference unit, an error amplifier, a current limit circuit, an under voltage lockout circuit (UVLO), and an over-voltage protection circuit (OVP). The R1203x can drive white LEDs in constant current with high efficiency by using an inductor, a diode, a resistor and capacitors as external components. The LEDs current can be set by an external resistance value and can adjust the dimming of LEDs by CE pin according to the signal of PWM. Feedback voltage is 0.2V, therefore power loss by current setting resistance is small and efficiency is good. Maximum duty cycle is internally fixed, Typ. 91%. LEDs can be driven from low voltage. Protection circuits are the current limit of Lx peak current, the over voltage limit of output, and the under voltage lockout function. It is controllable the dimming of LEDs quickly when the PWM signal (between 200Hz to 300kHz) input to CE pin. If the CE pin input is in the fixed time (Typ. 0.5ms), the IC becomes the standby mode and turns OFF LEDs. FEATURES Supply Current ....................................................... Typ. 500A Standby Current ..................................................... Max. 5A Input Voltage Range ............................................... 1.8V to 5.5V Feedback Voltage .................................................. 0.2V Feedback Voltage Accuracy ................................... 1.0% (10mV) Temperature-Drift Coefficient of Feedback Voltage ... 150ppm/C Oscillator Frequency............................................... Typ. 1.2MHz Maximum Duty Cycle ............................................. Typ. 91% Switch ON Resistance............................................ Typ. 1.35 UVLO Detector Threshold ....................................... Typ. 1.6V Lx Current Limit Protection ..................................... Typ. 700mA OVP Detector Threshold ......................................... Typ. 29.5V Switching Control ................................................... PWM LED dimming control .............................................. by external PWM signal (Frequency 200Hz to 300kHz) Packages .............................................................. DFN1616-6B, SOT-23-6 Ceramic capacitors are recommended ..................... 0.22F APPLICATION White LED Backlight for portable equipment 1 *R1203L(DFN1616-6B) is the non-promotional product of as February 2021. R1203x NO.EA-271-180703 SELECTION GUIDE The package for the ICs can be selected at the user s request. Product Name Package Quantity per Reel Pb Free Halogen Free R1203L071B-TR DFN1616-6B 5,000 pcs Yes Yes R1203N071B-TR-FE SOT-23-6 3,000 pcs Yes Yes BLOCK DIAGRAMS VFB VIN LX VOUT UVLO Err. Amp. PWM Comp. + + R Q Switch S Control OVP vref Oscillator PWM Cntrl Slope Com- Current Current pensation EN Protect sense Shutdown delay CE CE GND 2