RT5784A/B TM 2A, 6V, 1.5MHz, 25A I , ACOT Synchronous Step-Down Q Converter General Description Features Dramatically Fast Transient Response The RT5784A/B is a high-performance, Advanced Constant TM Steady 1.5MHz 200kHz Switching Frequency On-Time (ACOT ) monolithic synchronous step-down Very Low Input Quiescent and Shutdown Currents DC/DC converter that can deliver up to 2A output current Advanced COT Control Loop Design from a 2.5V to 6V input supply. The proprietary ACOT Optimized for Ceramic Output Capacitors control architecture features quick transient response and 2.5V to 6V Input Voltage Range provides stable operation with small ceramic output Accurate Voltage Reference 0.6V 2% capacitors and without complicated external Integrated 100m/60m MOSFETs compensation. The switching ripple voltage is easily Internal Start-Up into Pre-biased Outputs smoothed-out by small package filtering elements due to Power Good Indicator a constant switching frequency of 1.5MHz and the Enable Control maximum duty cycle of 100% allows the device to operate Over-Current and Over-Temperature Protections at low dropout use. With internal low on-resistance power Under-Voltage Protection with Hiccup Mode switches and extremely low quiescent current, the RoHS Compliant and Halogen Free RT5784A/B displays excellent efficiency and good behavior across a range of applications. Applications Cycle-by-cycle current limit provides protection against shorted outputs, input under-voltage lock-out, output Mobile Phones and Handheld Devices under-voltage protection, and thermal shutdown provide STB, Cable Modem, and xDSL Platforms safe and smooth operation in all operating conditions. The WLAN ASIC Power / Storage (SSD and HDD) RT5784A/B is available in the WDFN-8JL 2x1.5 (FC) General Purpose for POL LV Buck Converter package. Simplified Application Circuit L V IN VIN LX V OUT C IN R PGOOD RT5784A/B R1 C C OUT FF FB PGOOD PGOOD R2 Enable EN VOUT AGND PGND Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS5784A/B-02 January 2016 www.richtek.com 1RT5784A/B Ordering Information Pin Configurations RT5784 (TOP VIEW) Package Type QWF : WDFN-8JL 2x1.5 (FC) (W-Type) 1 8 EN PGOOD 2 7 FB VIN Lead Plating System AGND 3 6 LX G : Green (Halogen Free and Pb Free) VOUT 4 5 PGND PSM/PWM WDFN-8JL 2x1.5 (FC) A : PSM/PWM B : Force-PWM Note : Marking Information RT5784AGQWF Richtek products are : 01 : Product Code RoHS compliant and compatible with the current require- W : Date Code 01W ments of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. RT5784BGQWF 00 : Product Code W : Date Code 00W Functional Pin Description Pin No. Pin Name Pin Function Enable Control Input. Connecting this pin to logic high can enable the device and 1 EN connecting this pin to GND can disable the device. Feedback Voltage Input. This pin is used to set the desired output voltage via an 2 FB external resistive divider. The feedback reference voltage is 0.6V typically. Analog Ground. Provides the ground return path for control circuitry and internal 3 AGND reference. Output Voltage Sense Input. This pin is used to monitor and adjust output voltage for 4 VOUT superior load transient regulation. Power Ground. This pin must be soldered to a large PCB and connected to analog 5 PGND ground for maximum power dissipation. Switch Node. LX is the switching node that supplies power to the output and connect 6 LX the output LC filter from LX to the output load. Supply Input. Supplies the power to the internal control circuit as well as the power 7 VIN switches of the device. Drive VIN with a 2.5V to 6V power source and bypass VIN to PGND with a suitably large capacitor to eliminate noise on the input to the IC. Power Good Indicator Output. This pin is an open-drain logic output that is pulled to 8 PGOOD ground when the output voltage is lower or higher than its specified threshold under the conditions of UVP, OTP, dropout, EN shutdown, or during slow start. Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS5784A/B-02 January 2016 2