RT6232A/B TM 2A, 18V, 500kHz, ACOT Step-Down Converter General Description Features Integrated 210m/120m MOSFETs The RT6232A/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 2A output current from a 4.5V to 18V input ACOT Control supply. The RT6232A/B adopts ACOT architecture to 0.8V 1.5% Voltage Reference allow the transient response to be improved and keep Adjustable Soft-Start in constant frequency. Cycle-by-cycle current limit Power Good Indicator provides protection against shorted outputs and soft- Monotonic Start-Up into Pre-biased Outputs start eliminates input current surge during start-up. Fault Input Under-Voltage Lockout conditions also include output under voltage protection, Over-Current Protection and Hiccup output over current protection, and thermal shutdown. Applications Ordering Information Set-Top Boxes RT6232A/B Portable TVs Package Type QW : WDFN-8L 2x3 (W-Type) Access Point Routers DSL Modems Lead Plating System G : Green (Halogen Free and Pb Free) LCD TVs UVP Option H : Hiccup Marking Information A : PSM Mode RT6232AHGQW B : PWM Mode 0V : Product Code W : Date Code Note : 0VW Richtek products are : RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020. RT6232BHGQW 0U : Product Code Suitable for use in SnPb or Pb-free soldering processes. W : Date Code 0UW Simplified Application Circuit RT6232A/B V VIN IN BOOT C BOOT C IN L V LX OUT C OUT Enable EN R1 C FF PGOOD PGOOD FB R2 SS GND C SS Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation DS6232A/B-01 June 2015 www.richtek.com 1 RT6232A/B Pin Configurations (TOP VIEW) BOOT 1 8 SS GND 2 7 PGOOD 3 6 LX EN 4 9 5 VIN FB WDFN-8L 2x3 Functional Pin Description Pin No. Pin Name Pin Function Bootstrap Supply for High-Side Gate Driver. Connect a 100nF or greater 1 BOOT capacitor from LX to BOOT to power the high-side switch. 2, System Ground. Provides the ground return path for the control circuitry and GND 9 (Exposed Pad) 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. 4 VIN Power Input. Supplies the power switches of the device. Feedback Voltage Input. This pin is used to set the desired output voltage via 5 FB an external resistive divider. The feedback voltage is 0.8V typically. Enable Control Input. Floating this pin or connecting this pin to GND can disable 6 EN the device and connecting this pin to logic high can enable the device. Power Good Indicator Output. This pin is an open-drain logic output that is pulled to ground when the output voltage is lower or higher than its specified 7 PGOOD threshold under the conditions of OVP, OTP, dropout, EN shutdown, or during slow start. Soft-Start Control Input. Connect a capacitor from SS to GND to set the soft- 8 SS start period. Function Block Diagram BOOT VIN VIN PVCC Reg VCC UV &OV PVCC VIBIAS VREF Protection UGATE VCC OC LX Control Driver Ripple LGATE 1A Gen. + GND SS LX PGOOD FB Comparator FB + 0.9V - REF On-Time EN Comparator EN Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation www.richtek.com DS6232A/B-01 June 2015 2 - - GND