AOZ1037PI#A

AOZ1037 EZBuck™ 5A Synchronous Buck Regulator General Description Features The AOZ1037 is a high efficiency, simple to use, 5A synchronous buck regulator. The AOZ1037 works from a 4.5V to 18V input voltage range, and provides up to 5A of continuous output current with an output voltage adjustable down to 0.8V. z 4.5 to 18V operating input voltage range z Synchronous rectification: 55mΩ internal high-side switch and 19mΩ Internal low-side switch z High efficiency: up to 95% z Internal soft start The AOZ1037 comes in an exposed pad SO-8 packages and is rated over a -40°C to +85°C ambient temperature range. z Active high power good state z Output voltage adjustable to 0.8V z 5A continuous output current z Fixed 500kHz PWM operation z Cycle-by-cycle current limit z Pre-bias start-up z Short-circuit protection z Thermal shutdown z Exposed pad SO-8 package Applications z Point of load DC/DC conversion z LCD TVs z Set top boxes z DVD / Blu-ray players/recorders z Cable modems z PCIe graphics cards z Telecom/Networking/Datacom equipment Typical Application VIN 5V C1 22µF R3 VIN PGOOD L1 4.7µH EN AOZ1037 R1 COMP RC CC VOUT LX C2, C3 22µF FB AGND PGND R2 Figure 1. 3.3V/5A Synchronous Buck Regulator Rev. 1.1 September 2010 www.aosmd.com Page 1 of 14 AOZ1037 Ordering Information Part Number Ambient Temperature Range Package Environmental AOZ1037PI -40°C to +85°C EPAD SO-8 Green Product AOS Green Products use reduced levels of Halogens, and are also RoHS compliant. Please visit www.aosmd.com/web/quality/rohs_compliant.jsp for additional information. Pin Configuration PGND 1 VIN 2 AGND 3 FB 4 PAD (LX) 8 NC 7 PGOOD 6 EN 5 COMP Exposed Pad SO-8 (Top View) Pin Description Pin Number Pin Name 1 PGND 2 VIN Supply voltage input. When VIN rises above the UVLO threshold and EN is logic high, the device starts up. 3 AGND Analog ground. AGND is the reference point for controller section. AGND needs to be electrically connected to PGND. 4 FB Feedback input. The FB pin is used to set the output voltage via a resistor divider between the output and AGND. 5 COMP 6 EN 7 PGOOD 8 NC No Connect. Pin 8 is not internally connected. Pad LX Switching node. LX is the drain of the internal PFET. LX is used as the thermal pad of the power stage. Rev. 1.1 September 2010 Pin Function Power ground. PGND needs to be electrically connected to AGND. External loop compensation pin. Connect a RC network between COMP and AGND to compensate the control loop. Enable pin. Pull EN to logic high to enable the device. Pull EN to logic low to disable the device. if on/off control is not needed, connect it to VIN and do not leave it open. Power Good Output. PGOOD is an open-drain output that indicates the status of output voltage. PGOOD is pulled low when output is below 90% of the normal regulation. www.aosmd.com Page 2 of 14 AOZ1037 Block Diagram VIN UVLO & POR EN Internal +5V 5V LDO Regulator OTP + ISen – Reference & Bias Softstart Q1 ILimit + + 0.8V EAmp FB – – PWM Comp PWM Control Logic + Level Shifter + FET Driver LX Q2 COMP + 0.2V – 0.72V + 500kHz Oscillator Short Circuit Detection Comparator PGOOD – AGND PGND Absolute Maximum Ratings Recommended Operating Conditions Exceeding the Absolute Maximum ratings may damage the device. The device is not guaranteed to operate beyond the Maximum Recommended Operating Conditions. Parameter Supply Voltage (VIN) Rating Parameter 20V LX to AGND -0.7V to VIN+0.3V LX to AGND 23V (