RT7279GCP Richtek

RT7274/79/80/81 TM 2A, 18V, 700kHz ACOT Synchronous Step-Down Converter General Description Features TM zz z zz ACOT Mode Enables Fast Transient Response The RT7274/79/80/81 is a synchronous step-down DC/ TM zz z zz 4.5V to 18V Input Voltage Range DC converter with Advanced Constant On-Time (ACOT ) zz z zz 2A Output Current mode control. It achieves high power density to deliver up zz z zz High Efficient Internal N-MOSFET Optimized for to 2A output current from a 4.5V to 18V input supply. The TM Lower Duty Cycle Applications proprietary ACOT mode offers an optimal transient zz z zz 105m Internal Low-Side N-MOSFET response over a wide range of loads and all kinds of ceramic zz z zz Advanced Constant On-Time Control capacitors, which allows the device to adopt very low ESR zz z zz Allows Ceramic Output Capacitor output capacitor for ensuring performance stabilization. In zz z zz 700kHz Switching Frequency addition, RT7274/79/80/81 keeps an excellent constant zz z zz Adjustable Output Voltage from 0.765V to 8V switching frequency under line and load variation and the TM zz z zz Adjustable and Pre-biased Soft-Start integrated synchronous power switches with the ACOT zz z zz Cycle-by-Cycle Current Limit mode operation provides high efficiency in whole output zz z zz Input Under Voltage Lockout current load range. Cycle-by-cycle current limit provides zz z zz Thermal Shutdown an accurate protection by a valley detection of low-side zz z zz RoHS Compliant and Halogen Free MOSFET and external soft-start setting eliminates input current surge during startup. Protection functions include Applications thermal shutdown for RT7274/79/80/81 output under z Industrial and Commercial Low Power Systems voltage protection and output over voltage protection for z Computer Peripherals RT7279/80 only. z LCD Monitors and TVs z Green Electronics/Appliances z Point of Load Regulation for High-Performance DSPs, FPGAs, and ASICs Simplified Application Circuit RT7274/79/80/81 V IN VIN SW V OUT VINR* BOOT FB Input Signal EN Power Good GND* PGOOD* PVCC VOUT* SS PGND* * : VINR pin for TSSOP-14 (Exposed Pad) only. VOUT pin for TSSOP-14 (Exposed Pad) only. PGND pin for TSSOP-14 (Exposed Pad) and WDFN-10L 3x3 only. PGOOD pin for TSSOP-14 (Exposed Pad) and WDFN-10L 3x3 only. GND pin for TSSOP-14 (Exposed Pad) and SOP-8 (Exposed Pad) only. Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS7274/79/80/81-02 April 2013 www.richtek.com 1RT7274/79/80/81 Ordering Information Marking Information Discontinuous Operating Mode RT7274GSP RT7274 RT7274GSP : Product Number RT7274 YMDNN : Date Code Package Type GSPYMDNN SP : SOP-8 (Exposed Pad-Option 2) Lead Plating System G : Green (Halogen Free and Pb Free) RT7280GCP RT7280GCP : Product Number RT7280 YMDNN : Date Code RT7280 GCPYMDNN Package Type CP : TSSOP-14 (Exposed Pad) RT7280GQW QW : WDFN-10L 3x3 (W-Type) 2Y= : Product Code Lead Plating System YMDNN : Date Code 2Y=YM G : Green (Halogen Free and Pb Free) DNN Forced PWM Mode RT7279GCP RT7279GCP : Product Number RT7279 RT7279 YMDNN : Date Code Package Type GCPYMDNN CP : TSSOP-14 (Exposed Pad) QW : WDFN-10L 3x3 (W-Type) RT7279GQW Lead Plating System 2Z= : Product Code G : Green (Halogen Free and Pb Free) YMDNN : Date Code 2Z=YM DNN RT7281 RT7281GSP Package Type RT7281GSP : Product Number SP : SOP-8 (Exposed Pad-Option 2) RT7281 YMDNN : Date Code Lead Plating System GSPYMDNN G : Green (Halogen Free and Pb Free) Pin Configurations (TOP VIEW) 14 VOUT VINR 2 13 FB VIN 3 12 PVCC BOOT 8 EN VIN EN 1 10 VIN 4 11 PGND SS SW 9 2 2 7 FB VIN FB BOOT GND 5 10 SW GND 3 PVCC 8 BOOT 3 6 PVCC SW 6 9 PGND PGOOD 15 4 7 9 SS SW 7 8 4 5 EN PGND SS GND 5 11 6 SW PGOOD TSSOP-14 (Exposed Pad) WDFN-10L 3x3 SOP-8 (Exposed Pad) Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS7274/79/80/81-02 April 2013 2 PGND