RT2657GQW

RT2657 2.25MHz 600mA Synchronous Step-Down Converter General Description Features V Range 2.7V to 5.5V IN The RT2657 is a high efficiency Pulse-Width-Modulated V Range 0.6V to 5.5V (100% Duty Ratio Operation) OUT (PWM) step-down DC/DC converter, capable of delivering V = 0.6V REF 600mA output current over a wide input voltage range from I 5A (V = 0V) SD EN 2.7V to 5.5V. The RT2657 is ideally suited for portable Current Mode Control, Internal Compensation electronic devices that are powered from 1-cell Li-ion Fixed F 2.25MHz SW battery or from other power sources such as cellular R 230m HS/250m LS (P-MOSFET/ DS(ON) phones, PDAs, hand-held devices, game console and N-MOSFET) related accessories. Enable (V = 1V, V = 0.4V) Int. Soft-Start (0.3ms) IH IL The internal synchronous rectifier with low R DS(ON) Up to 600mA Output Current dramatically reduces conduction loss at PWM mode. Up to 90% Efficiency No external Schottky diode is required in practical Peak I (1.5A Typical / 0.8A Min) UVLO UVP LIMIT applications. The RT2657 enters Low Dropout Mode when V and V OVP and OTP (150C) IN OUT normal Pulse -Width Mode cannot provide regulated output No Schottky Diode Required voltage by continuously turning on the upper P-MOSFET. Internal Compensation to Reduce External The RT2657 enters shut-down mode and consumes less Components than 5A when the EN pin is pulled low. The switching RoHS Compliant and Halogen Free ripple is easily smoothed-out by small package filtering elements due to a fixed operating frequency of 2.25MHz. Applications The RT2657 is available in the small WDFN-6SL 2x2 Portable Instruments package. Game Console and Accessories Microprocessors and DSP Core Supplies Marking Information Cellular Phones 1W : Product Code Wireless and DSL Modems W : Date Code PC Cards 1WW Automotive InfoTainMent Simplified Application Circuit RT2657 L1 V LX VIN V IN OUT C IN C1 C R1 OUT EN FB R2 GND Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS2657-00 November 2013 www.richtek.com 1RT2657 Ordering Information Pin Configurations RT2657 (2) (TOP VIEW) Taping Type ( Pin1 at Q2) 1 6 LX GND Package Type NC 2 5 VIN QW : WDFN-6SL 2x2 (W-Type) 3 7 4 FB EN Lead Plating System WDFN-6SL 2x2 G : Green (Halogen Free and Pb Free) Note : Richtek products are : RoHS compliant and compatible with the current require- ments of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. Function Pin Description Pin No. Pin Name Pin Function 1 LX Switch Node. Connect to the external inductor. 2 NC No Internal Connection. Connect to GND. 3 FB Feedback Voltage Input. Connect to the external resistor divider. 4 EN Enable Control Input (Active High). 5 VIN Power Input. Connect to the input capacitor. 6, Power GND. The Exposed Pad must be soldered to a large PCB and connected GND 7 (Exposed Pad) to GND for maximum power dissipation. Function Block Diagram EN VIN R S1 OSC & Current Shutdown Limit Control Detector Slope Compensation Current Sense Error Control Driver Amplifier LX Logic FB PWM Comparator R C R S2 COMP UVLO & GND Power Good Detector V REF Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS2657-00 November 2013 2 GND