R1200x Series PWM Step-up DC/DC Converter for PMOLED and General Use with shutdown function The R1200x Series are CMOS-based PWM step-up DC/DC converters, which are optimized to drive PMOLED or white LEDs with constant current. The R1200x includes an under-voltage lockout circuit (UVLO), a soft-start circuit, and an over-voltage protection circuit (OVP). By simply using an inductor, divider resistors, and capacitors as external components, PMOLEDs and white LEDs can be driven with high efficiency. At the standby mode, the internal NPN transistor can separate the output from the input. (Shutdown function) By this shutdown function, the LED current can be completely shutdown, and output voltage for PMOLED can be completely cut off, therefore, the R1200x does not have bad impact on the life expectancy of PMOLED. The version with auto-discharge function is available. FEATURES • Supply Current (IDD) ··················· Typ. 500μA (No switching) • Standby Current (Istandby) ·············· Typ. 0μA (CE="L") • Input Voltage Range (VIN) ············ 2.3V to 5.5V • UVLO Detect Voltage (VUVLO1) ······ Typ. 2.0V • Coil-current Limit Circuit ·············· Current limit Typ. 700mA • Over Voltage Protection Circuit (OVP) • Soft Start Time (tstart) ··················· Typ. 1.5ms • Shutdown Function • Auto-discharge Function·············· A Version • Packages ································· DFN1616-6, DFN(PLP)1820-6, (Absolute maximum rating: 6.5V) • Output Voltage Range (VOUT) ······· Externally adjustable • Feedback Voltage (VFB) ··············· 1.0V • Feedback Voltage Accuracy ········· ± 15mV • Temp. Coeff. of Feedback Voltage ····· ± 150ppm/°C • Oscillator Frequency (fosc) ············ 1.2MHz • Oscillator Maximum Duty Cycle (Maxduty) ·· Min. 86%, Typ. 91% SOT-23-6 BLOCK DIAGRAMS TYPICAL APPLICATION R1200xxxxA (With Auto-discharge function) VFB VIN By simply using an inductor, divider resistors and capacitors as external components, a high-efficiency step-up DC/DC converter can be easily configured. R1200xxxxB LX (Without Auto-discharge function) VOUT VFB VIN UVLO LX VOUT L1 22μH UVLO Error Amp Error Amp PWM Comp C1 1μF PWM Comp R Q S Switching Control R Q S OVP Vref Switching Control OSC Chip Enable Soft Start LX VOUT C3 Current Sense Current Protection CE Chip Enable Soft Start Slope Compensation VIN OVP Vref OSC Slope Compensation Current Protection R2 Current Sense GND Σ VFB Σ GND CE C2 1μF R3 R1 GND ∗ R1, R2 : For setting output voltage R3 : 2kΩ, C3 : 220pF CE SELECTION GUIDES Package DFN1616-6 DFN(PLP)1820-6 SOT-23-6 Q'ty per Reel Part No. 5,000 pcs R1200L.xxx$ -TR 5,000 pcs R1200K.xxx$ -TR 3,000 pcs R1200N.xxx$ -TR-FE PACKAGES (Top View) DFN1616-6 6 5 DFN(PLP)1820-6 6 4 5 1 2 3 4 5 6 2 3 CE VFB LX GND VIN VOUT SOT-23-6 5 R1200x 1 1 2 3 4 5 6 2 3 CE VFB LX GND VIN VOUT ∗) The tab is substrate level (GND). Efficiency vs. Output Current 4 VIN=3.6V VOUT=15V 90 ∗ ∗ 1 TYPICAL CHARACTERISTIC 6 4 .xxx : Specify the OVP voltage. .001.: OVP : 17V, .002.: OVP : 19V, .003.: OVP : 21V .$. : Select from (.A.) with auto-discharge function or (.B.) without auto-discharge function 80 1 1 2 3 4 5 6 2 3 CE VOUT VIN LX GND VFB Efficiency η (%) Halogen Free 70 60 50 40 30 LQH32CN220K53 (22μH) LQH32CN100K53 (10μH) LQH32CN4R7M53 (4.7μH) 20 10 0 0 20 40 60 Output Current IOUT (mA) 80 APPLICATIONS • PMOLED power supply for hand-held equipment No.EK-192-140930 • White LED driver for hand-held equipment • Step-up DC/DC Converter R1200x Series Step-up DC/DC Converter Step-up DC/DC Converter for OLED Back Light with shutdown function The Shutdown Function Due to the typical step-up DC/DC converter circuit, a voltage may appear at the output of the circuit even if the driver IC is in the standby mode. A current flows from the battery, through the inductor and diode to the output pins. In case an OLED display is connected, it is powered constantly and it may have an impact to the lifetime of the OLED. In addition, when the input voltage is close to the Vf voltage of a white LED, it is unable to turn these off properly. The R120xx Series have an internal NPN transistor instead of a diode. In standby mode, the NPN transistor turns off and isolates the current flow from input to output. . VIN VIN LX LX VOUT VOUT CE CE VFB GND VFB GND R1218x R1200x Comparison of PMOLED and General Use DC/DC Converter Product Name R1200x R1202xxxxA/B Control PWM PWM 2.3V to 5.5V Ext. adjustable (Up to 20.0V） (VFB=1.0V) ±15mV 1.2MHz Internal 700mA TYP. 2.0V TYP. 1.5ms 2.3V to 5.5V Ext. adjustable (Up to 22.2V） (VFB=1.0V) ±15mV 1.2MHz Internal 350mA, 700mA TYP. 2.0V TYP. 2ms PWM(B/E), PWM/VFM Auto Switching (C/F) 2.3V to 5.5V Ext. adjustable (Up to 40.2V） (VFB=1.0V) ±15mV 750kHz(E/F), 1MHz(B/C) External 900mA TYP. 2.0V TYP. 10ms 17.0V, 19.0V, 21.0V 14.0V, 17.0V, 19.0V, 21.0V, 23.0V 23.0V, 33.0V, 42.0V DFN1616-6, DFN(PLP)1820-6, SOT-23-6 Shutdown Function Auto-discharge Function (A) DFN1616-6B, TSOT-23-6 DFN(PLP)1820-6, TSOT-23-6 Shutdown Function Auto-discharge Function (A) Thermal Shutdown Circuit Thermal Shutdown Circuit Input Voltage Range Output Voltage Range Feedback Voltage Accuracy Oscillator Frequency Diode Coil-current Limit Circuit UVLO Detect Voltage Soft Start Time Over Voltage Protection Circuit Package Others R1204xxxxB/C/E/F The currently available information as of September 2014 is provided in this New Product News. EK-192-140930