RT8463GQW

RT8463 High Voltage Multi-Topology LED Driver General Description Features zz z zz High Voltage : V Up to 50V, V Up to 50V IN OUT The RT8463 is a current mode PWM regulator for LED zz z zz Buck, Boost or Buck-Boost Operation driving applications. With a 2A power switch, wide input zz z zz Built-In 2A Power Switch voltage (4.5V to 50V) and output voltage (up to 50V) zz z zz Current Mode PWM Control ranges, the RT8463 can operate in any of the three zz z zz 470kHz Fixed Switching Frequency common topologies : Buck, Boost or Buck-Boost. zz z zz Easy Dimming : Analog, PWM Digital or PWM With 470kHz operating frequency, the size of the external Converting to Analog with One External Capacitor PWM inductor and input/output capacitors can be zz z zz Adjustable Soft-Start to Avoid Inrush Current minimized. High efficiency is achieved by a 100mV current zz z zz Adjustable Over Voltage Protection to Limit Output sensing control. Voltage Brightness dimming can be controlled from either analog zz z zz Thermal Shutdown or PWM signal. A unique built-in clamping comparator zz z zz Under Voltage Lockout and filtering resistor allow easy low noise analog dimming zz z zz RoHS Compliant and Halogen Free conversion from PWM signal with only one external capacitor. Applications z GPS, Portable DVD Backlight The RT8463 is available in the TSSOP-14 (Exposed pad) z Desk Lights and Room Lighting and WDFN-12L 3x3 packages. z Industrial Display Backlight Ordering Information Marking Information RT8463 Package Type RT8463GCP CP : TSSOP-14 (Exposed Pad) RT8463GCP : Product Number QW : WDFN-12L 3x3 (W-Type) RT8463 YMDNN : Date Code GCPYMDNN Lead Plating System G : Green (Halogen Free and Pb Free) Note : RT8463GQW Richtek products are : 98 = : Product Code RoHS compliant and compatible with the current require- YMDNN : Date Code 98=YM ments of IPC/JEDEC J-STD-020. DNN Suitable for use in SnPb or Pb-free soldering processes. Simplified Application Circuit D1 L V V IN OUT C1 C6 RT8463 VCC SW R2 EN 5V ISP DCTL ISN PWM R3 Dimming Control V OVP OUT VC SS CREG R4 R1 C5 C3 ACTL GND C4 C2 Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS8463-00 January 2013 www.richtek.com 1RT8463 Pin Configurations (TOP VIEW) 14 ISP VCC 2 13 12 ISN CREG ISP 1 VCC 11 ISN 2 3 12 CREG VC SW 3 10 VC SW 4 11 GND ACTL GND GND 4 9 GND ACTL 5 10 DCTL SS 5 8 SS DCTL 6 9 13 EN67 OVP EN OVP 15 7 8 GND GND TSSOP-14 (Exposed Pad) WDFN-12L 3x3 Functional Pin Description Pin No. Pin Name Pin Function TSSOP-14 WDFN-12L 3x3 (Exposed Pad) 1 1 ISP Positive Current Sense Input. Negative Current Sense Input. Voltage threshold between ISP and 2 2 ISN ISN is 100mV. 3 3 VC Compensation Node for PWM Boost Converter Loop. Analog Dimming Control Input. Effective programming range is 4 4 ACTL between 0.2V and 1.2V. Digital Dimming Control Input. By adding a 0.47 F filtering capacitor on the ACTL pin, the PWM dimming signal on DCTL pin 5 5 DCTL will be averaged and converted into analog dimming signal on the ACTL pin. V = 1.2V x PWM dimming duty cycle. ACTL Enable Control Input (Active High). When this pin is low, the chip is 6 6 EN in shutdown mode. 7, 8, 11, 15 9, Ground. The exposed pad must be soldered to a large PCB and GND (Exposed Pad) 13 (Exposed Pad) connected to GND for maximum power dissipation. Over Voltage Protection Sense Input. The PWM Boost converter 9 7 OVP turns off when V goes higher than 1.2V. OVP Soft-Start Time Setting. A minimum 10nF capacitor is required for 10 8 SS soft-start. 12 10 SW Switch Node of PWM Boost Converter. Regulator Output for Internal Circuit. Placed a 1 F capacitor to 13 11 CREG stabilize the 5V output regulator. Power Supply Voltage Input. For good bypass, a low ESR 14 12 VCC capacitor is required. Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS8463-00 January 2013 2