RT8482GQW Richtek

RT8482 High Voltage High Current LED Driver Controller for Buck Boost, or Buck-Boost Topology General Description Features zz z zz High Voltage Capability : V Up to 36V, V Up to IN OUT The RT8482 is a current mode PWM controller designed 48V to drive an external MOSFET for high current LED zz z zz Buck, Boost or Buck-Boost Operation applications. With a current sense amplifier threshold of zz z zz Current Mode PWM with 350kHz Switching 190mV, the LED current is programmable with one Frequency external current sense resistor. With a maximum zz z zz Easy Dimming : Analog, PWM Digital or PWM operating input voltage of 36V and output voltage up to Converting to Analog with One External Capacitor 48V, the RT8482 is ideal for Buck, Boost or Buck-Boost zz z zz Programmable Soft Start to Avoid Inrush Current operation. zz z zz Programmable Over Voltage Protection With 350kHz operating frequency, the external inductor zz z zz V Under Voltage Lockout and Thermal Shutdown IN and capacitors can be small while maintaining high zz z zz 16-Lead WQFN and SOP Packages efficiency. zz z zz RoHS Compliant and Halogen Free Dimming can be either analog or PWM digital. The unique built-in clamping comparator and filter allow easy low Applications noise analog dimming conversion from PWM signal with z General Industrial High Power LED Lighting only one external capacitor. z Desk Lights and Room Lighting The RT8482 is available in WQFN-16L 3x3 and z Building and Street Lighting SOP-16 packages. z Industrial Display Backlight Ordering Information Marking Information RT8482 RT8482GS Package Type S : SOP-16 RT8482GS : Product Number QW : WQFN-16L 3x3 (W-Type) RT8482 YMDNN : Date Code GSYMDNN Lead Plating System G : Green (Halogen Free and Pb Free) Note : RT8482GQW Richtek products are : H9= : Product Code RoHS compliant and compatible with the current require- YMDNN : Date Code H9=YM ments of IPC/JEDEC J-STD-020. DNN Suitable for use in SnPb or Pb-free soldering processes. Copyright 2012 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS8482-02 May 2012 www.richtek.com 1RT8482 Pin Configurations (TOP VIEW) GBIAS 16 GND 16 15 14 13 2 15 GATE VCC GBIAS 1 12 NC 3 14 NC OVP 2 11 GATE SS ISW 4 13 EN GND 5 12 NC 3 10 DCTL NC NC 17 6 11 ISW 4 9 ACTL ISP SS 7 10 ISN DCTL 5 6 7 8 8 9 VC ACTL SOP-16 WQFN-16L 3x3 Typical Application Circuit L1 R SENSE D1 47H 0.09 V OUT V IN 48V (Max.) C 4.5V to 36V IN C OUT 10F 1F RT8482 M1 2 15 GATE VCC R SW 13 0.05 EN 5V 4 ISW Analog 9 ACTL 6 Dimming ISP 10 7 DCTL ISN 8 R1 VC 14 V OVP OUT R 11 VC SS 1 10k GBIAS R2 C B C SS C 1F VC 0.1F 3.3nF GND 16, 17 (Exposed Pad) Figure 1. Analog Dimming in Boost Configuration R L1 SENSE 47H D1 0.09 V OUT V IN 48V (Max.) 4.5V to 36V C IN C OUT 10F 1F RT8482 M1 15 2 GATE VCC R SW 0.05 13 EN 4 5V ISW 10 6 DCTL ISP PWM Dimming control 7 ISN 8 VC R1 14 V OVP OUT R VC 11 SS 10k 1 GBIAS 9 R2 ACTL C C SS B C VC 1F 0.1F 3.3nF C A GND 0.47F 16, 17 (Exposed Pad) Figure 2. PWM to Analog Dimming in Boost Configuration Copyright 2012 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS8482-02 May 2012 2 NC GND ISP VCC ISN OVP VC EN