XX-XXXX; Rev 0; 7/07 Dual, 5A, 1.5MHz Step-Down Regulator with Integrated High-Side Switches Features The MAX8653 dual-output, synchronous, step-down regulator contains low R DS(ON) integrated high-side MOSFET switches for ease of layout and achieving small footprints. Each output delivers up to 5A. The output voltage is adjustable down to 0.6V and operates from a 9V to 14V input voltage. The MAX8653 uses a proprietary high-bandwidth, constant-frequency, peak-voltage-mode control architecture and operates at an adjustable switching frequency between 300kHz to 1.5MHz. The architecture is suitable for use with a wide range of output capacitor technologies such as aluminum electrolytic, POSCAPs, and ceramic capacitors for flexible design. The simple compensation scheme achieves fast response under both line and load transients. The switching frequency is adjustable using a single external resistor. The output channels operate 180° outof-phase to reduce the input ripple current, thus reducing the required input capacitance. The high operating frequency minimizes the size of external components. The external reference input (REFIN) enables implementation of tracking applications such as DDR power supplies. The MAX8653 utilizes internal digital soft-start and features a lossless (cycle-by-cycle) current sensing. It includes adjustable, hiccup-mode current-limit and short-circuit protection for minimum power dissipation under fault conditions. Each output contains an enable (EN_) input along with a power-good (POK_) signal for easy sequencing. The MAX8653 is available in a 28-pin, 5mm x 5mm Thin QFN package. M IN A R Y ♦ Integrated 80mΩ RDS(ON), High-Side MOSFETs ♦ Adjustable Hiccup-Mode Short-Circuit CurrentLimit Protection ♦ ±1% Output Accuracy over Load, Line, and Temperature ♦ 9V to 14V Input Supply Range ♦ Adjustable Output Down to 0.6V ♦ Digital Soft-Start Reduces Inrush Supply Current ♦ 300kHz to 1.5MHz Adjustable Switching Frequency ♦ External Frequency Synchronization ♦ Compatible with Ceramic, Polymer, and Electrolytic Capacitors ♦ 180° Out-of-Phase Operation ♦ Enable and POK for Each Output ♦ REFIN Feature for Tracking Applications ♦ 28-Lead 5mm x 5mm Thin QFN Package E LI Typical Operating Circuit IN2 POK1 POK2 BST1 BST2 LX1 LX2 MAX8653 DL1 OUTPUT2 3.3V, 2A REFIN AGND AVL VL PGND OSC SYNC DL2 FB1 ILIM1 EN1 T2855-5 FB2 ILIM2 EN2 R P OUTPUT 1.5V, 5A 28 Thin QFN-EP** (5mm x 5mm) PKG CODE Pin Configuration appears at end of data sheet. V+ IN1 PIN-PACKAGE +Denotes lead-free package. *The MAX8653 is specified in the extended temperature range. **EP = Exposed pad. DDR Memories DSL Set-Top Box Cable Modem INPUT 9V TO 14V TEMP RANGE* MAX8653ETI+ -40°C to +85°C Applications Telecom Network Equipment Storage Servers PART Ordering Information ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. 1 MAX8653 General Description