RT9203PS

Preliminary RT9203/A Dual Regulators - Synchronous Buck PWM DC-DC and Linear Controller General Description The RT9203/A is a dual-output power controllers designed for high performance graphics cards and personal computers. The IC integrates a synchronous buck controller, a linear controller and protection functions into a small 8-pin package. The RT9203/A uses an internal compensated voltage mode PWM control for simplying design. An internal 0.8V reference allows the output voltage to be precisely regulated to meet low output voltage requirement. A fixed 300kHz oscillation frequency reduces the component size for saving board area. The RT9203/A also features over voltage protection (OVP) and under voltage lock-out (UVLO). Features l l l l l l l l l l l l Operates at 5V 0.8V Internal Reference Drives Two N-MOSFET Voltage Mode PWM Control Fast Transient Response Fixed 300kHz Oscillator Frequency Dynamic 0 to 100% Duty Cycle Internal PWM Loop Compensation Internal Soft-Start Adaptive Non-Overlapping Gate Driver Over-Voltage Protection Uses Lower MOSFET RoHS Compliant and 100% Lead (Pb)-Free Applications l l l l Ordering Information RT9203/A Package Type S : SOP-8 Operating Temperature Range P : Pb Free with Commercial Standard G : Green (Halogen Free with Commercial Standard) UVP : Hiccup Mode UVP : Latch Mode Note : RichTek Pb-free and Green products are : }RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020. }Suitable for use in SnPb or Pb-free soldering processes. }100%matte tin (Sn) plating. l l l l l PC Motherboard Cable Modems, Set-Top-Box, and DSL Modems DSP and Core Communications Processor Supplies Memory Power Supplies Personal Computer Peripherals Industrial Power Supplies 5V Input DC-DC Regulators Low Voltage Distributed Power Supplies Graphic Cards Pin Configurations (TOP VIEW) BOOT UGATE GND LGATE 2 3 4 8 7 6 5 FB FBL DRV VCC SOP-8 DS9203/A-10 March 2007 www.richtek.com 1 www.richtek.com 2 RT9203/A 5V 5V Typical Application Circuit 5V + 1uF 1N5819 5 + VCC 6 PHASE UGATE 4 8 1uF D2 5 Phase 2 2 G1 3 S2 4 G2 D1 7 D2 6 1uF BOOT 1 680uF 5uH P hase PHKD6N02LT 0.1uF 8 1 S1 D1 100uF 1uH Be Careful during Layout 2SD1802 VOUT1 1.6V VOUT2 FBL FB RT9203/A G ND 120