EN5337QI 3A Voltage Mode Synchronous Buck PWM DC-DC Converter with Integrated Inductor Description Features The EN5337QI is a Power Supply on a Chip Integrated Inductor, MOSFETS, Controller 2 (PwrSoC) DC-DC converter. It integrates Total Power Solution 75mm MOSFET switches, all small-signal circuits, Minimal external components. compensation, and the inductor in an advanced 3A Continuous Output Current Capability 4mm x 7mm QFN package. 5MHz operating frequency. Switching The EN5337QI is specifically designed to meet frequency can be phase locked to an external the precise voltage and fast transient clock. requirements of present and future high- High efficiency, up to 92%. performance, low-power processor, DSP, FPGA, Wide input voltage range of 2.375V to 5.5V. memory boards, and system level applications in distributed power architectures. Advanced circuit Output Enable pin and Power OK signal. techniques, ultra high switching frequency, and Programmable soft-start time. very advanced, high-density, integrated circuit Under Voltage Lockout, Over Current, Short and proprietary inductor technology deliver high- Circuit and Thermal Protection. quality, ultra compact, non-isolated DC-DC RoHS compliant, MSL level 3, 260C reflow. conversion. The Enpirion solution significantly helps in Applications system design and productivity by offering greatly Point of load regulation for low-power simplified board design, layout and processors, network processors, DSPs, manufacturing requirements. In addition, a FPGAs, and ASICs reduction in the number of vendors required for Noise sensitive applications such as A/V, RF the complete power solution helps to enable an and Gbit I/O overall system cost savings. Low voltage, distributed power architectures All Enpirion products are RoHS compliant and with 2.5V, 3.3V or 5V rails lead-free manufacturing environment compatible. Computing, Networking, DSL, STB, DVR, DTV, iPC Ripple sensitive applications RA 0402 0402 RB 0402 Soft Start Cap CA 0402 Beat frequency sensitive applications V V OUT IN PVIN VOUT RA EN5337QI ENA 22 F CA AVIN XFB 1206 47 F 1206 PGND PGND SS Output Cap Input Cap RB AGND 47uF/1206 22uF/1206 Figure 1: Total Solution Footprint (Not to scale) 2 Total Area 75 mm Figure 2: Typical Application Schematic www.enpirion.com 02638 September 12, 2012 Re v: E EN5337QI EN5337QI Ordering Information Pin Assignments (Top View) Temp Rating 38 37 36 35 34 33 32 31 30 28 29 27 26 Part Number (C) Package NC(SW) 1 25 NC EN5337QI -40 to +85 38-pin QFN T&R EN5337QI-E QFN Evaluation Board NC(SW) 2 24 NC 3 NC 23 NC EN5337QI NC 4 22 NC VOUT 5 PVIN 21 VOUT 6 20 PVIN 15 16 78 910 11 12 13 14 17 18 19 Figure 3: Pinout Diagram (Top View) NOTE: All perimeter pins must be soldered to PCB. Pin Description PIN NAME FUNCTION NO CONNECT These pins are internally connected to the common switching node of the 1-2, 12, NC(SW) internal MOSFETs. They are not to be electrically connected to any external signal, ground, 34-38 or voltage. Failure to follow this guideline may result in damage to the device. NO CONNECT These pins may be internally connected. Do not connect them to each 3-4, NC other or to any other electrical signal. Failure to follow this guideline may result in device 22-25 damage. Regulated converter output. Connect these pins to the load, and place output capacitor 5-11 VOUT from these pins and PGND pins 13-15 Input/Output power ground. Connect these pins to the ground electrode of the Input and 13-18 PGND output filter capacitors. See VOUT and PVIN pin descriptions for more details. Input power supply. Connect to input power supply. Decouple with input capacitor to 19-21 PVIN PGND pins 16-18. 26 SYNC External Clock Input to synchronize internal switching clock to an external signal Input Enable. Applying logic high enables the output and initiates a soft-start. Applying a 27 ENABLE logic low disables the output. Power OK is an open drain transistor for power system state indication. POK will be logic 28 POK high when VOUT is with -10% to +20% of VOUT nominal. 29 EAOUT Optional Error Amplifier output. Allows for customization of the control loop response. Soft-Start node. The soft-start capacitor is connected between this pin and AGND. The 30 SS value of this capacitor determines the startup time. External Feedback Input. The feedback loop is closed through this pin. A voltage divider at 31 XFB VOUT is used to set the output voltage. The mid point of the divider is connected to XFB. A phase lead capacitor from this pin to VOUT is also required to stabilize the loop. Analog Ground. This is the Ground return for the controller. Needs to be connected to a 32 AGND quiet ground. Input power supply for the controller. Needs to be connected to input voltage at a quiet 33 AVIN point. Enpirion 2012 all rights reserved, E&OE 2 www.enpirion.com 02638 September 12, 2012 Rev: E VOUT NC(SW) VOUT NC(SW) VOUT NC(SW) VOUT NC(SW) VOUT NC(SW) NC(SW) AVIN PGND AGND PGND XFB PGND SS PGND EAOUT PGND POK PGND ENABLE PVIN SYNC