RT6211AHGE Richtek

RT6211A/B TM 1.5A, 18V, 500kHz, ACOT Step-Down Converter General Description Features Integrated 230m/130m MOSFETs The RT6211A/B is a high-efficiency, monolithic 4.5V to 18V Supply Voltage Range synchronous step-down DC/DC converter that can 500kHz Switching Frequency deliver up to 1.5A output current from a 4.5V to 18V ACOT Control input supply. The RT6211A/B adopts ACOT 0.8V 1.5% Voltage Reference architecture to allow the transient response to be Internal Start-Up from Pre-biased Output improved and keep in constant frequency. Voltage Cycle-by-cycle current limit provides protection against Compact Package : SOT-23-6 pin shorted outputs and soft-start eliminates input current High/Low Side Over-Current Protection and surge during start-up. Fault conditions also include Hiccup output under voltage protection, output over current V Range 0.8V to 6.5V OUT protection, and thermal shutdown. Applications Ordering Information Set-Top Boxes RT6211A/B Portable TVs Package Type Access Point Routers E : SOT-23-6 DSL Modems Lead Plating System LCD TVs G : Green (Halogen Free and Pb Free) UVP Option Marking Information H : Hiccup RT6211AHGE 3J= : Product Code A : PSM Mode DNN : Date Code B : PWM Mode 3J=DNN Note : RT6211BHGE Richtek products are : 39= : Product Code DNN : Date Code RoHS compliant and compatible with the current 39=DNN requirements of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. Simplified Application Circuit RT6211A/B BOOT C BOOT V VIN IN C IN L V LX OUT C OUT Enable EN R1 C FF FB GND R2 Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS6211A/B-02 September 2015 www.richtek.com 1 RT6211A/B Pin Configurations (TOP VIEW) ENBOOT FB 654 23 GND VINLX SOT-23-6 Functional Pin Description Pin No. Pin Name Pin Function 1 VIN Power Input. Supplies the power switches of the device. System Ground. Provides the ground return path for the control circuitry and 2 GND low-side power MOSFET. Switch Node. LX is the switching node that supplies power to the output and 3 LX connect the output LC filter from LX to the output load. Bootstrap Supply for High-Side Gate Driver. Connect a 100nF or greater 4 BOOT capacitor from LX to BOOT to power the high-side switch. Enable Control Input. Floating this pin or connecting this pin to logic high can 5 EN enable the device and connecting this pin to GND can disable the device. Feedback Voltage Input. This pin is used to set the desired output voltage via 6 FB an external resistive divider. The feedback voltage is 0.8V typically. Function Block Diagram BOOT VIN VIN PVCC Reg Minoff PVCC VIBIAS VREF UGATE OC LX Control Driver LGATE UV &OV GND GND LX PVCC EN EN Ripple VIN LX + Gen. On-Time LX Comparator FB Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS6211A/B-02 September 2015 2 --