MP38873DL-LF-P Monolithic Power Systems

MP38873 15A, 16V, High Frequency Step-Down Converter with Synchronous Gate Driver The Future of Analog IC Technology DESCRIPTION FEATURES The MP38873 is a monolithic step-down switch Wide 4.5V to 16V Operating Input Range mode converter with a built in internal power 15A Output Current MOSFET. It achieves 15A continuous output 25m Internal Power MOSFET Switch current over a wide input supply range with Synchronous Gate Driver excellent load and line regulation. Synch from 300KHz to > 1MHz External Clock or 400KHz Fixed Switching Frequency Current mode operation provides fast transient Synch Output to Drive Another Regulator in response and eases loop stabilization. Phase-Shift Operation Fault condition protection includes cycle-by-cycle Feedback Voltage Accuracy: 2% current limiting and thermal shutdown. Programmable Soft-Start The MP38873 requires a minimum number of Startup Tracking readily available standard external components EN and Power Good for Power Sequencing and is available in a 20-pin 3mm x 4mm QFN Cycle-by-Cycle Over Current Protection package. Thermal Shutdown Output Adjustable from 0.8V to 12V The MP38873 is ideal for a wide range of Stable with Low ESR Output Ceramic applications including distributed power systems, Capacitors pre-regulator for linear regulators, compact DC- DC regulators for PCB space limited platforms. Available in a 3mm x 4mm QFN Package APPLICATIONS Distributed Power Systems Pre-Regulator for Linear Regulators Compact DC-DC Regulator for PCB Space Limited Platforms MPS and The Future of Analog IC Technology are Registered Trademarks of Monolithic Power Systems, Inc. TYPICAL APPLICATION VCC Efficiency vs. Output Current V =12V,V =1.2V IN OUT System 95 V IN PG BST IN 90 85 V OUT SW 1.2V/15A COMP 80 M2 R3 VCC 75 BG MP38873 70 SS/TRK C6 C3 FB 65 60 OFF ON EN 55 SYNCIN SYNCOUT GND 50 0 2 4 6 8 10 12 14 16 OUTPUT CURRENT(A) MP38873 Rev. 0.9 www.MonolithicPower.com 1 9/17/2009 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. 2009 MPS. All Rights Reserved. EFFICIENCY (%)MP38873 15A, 16V, HIGH FREQUENCY STEP-DOWN WITH SYNCHRONOUS GATE DRIVER (1) PACKAGE REFERENCE ABSOLUTE MAXIMUM RATINGS Supply Voltage V ....................................... 18V TOP VIEW IN V ....................... 0.3V (-5V for < 10ns) to 19V SW PIN 1 ID GND GATE VIN V ....................................................... V + 6V BS SW 20 19 18 All Other Pins.................................0.3V to +6V VCC 1 17 Junction Temperature...............................150C 16 SYNCOUT 2 Lead Temperature ....................................260C Storage Temperature ..............65 C to +150 C SYNCIN 3 15 (2) Recommended Operating Conditions EN 4 VIN 14 SW Supply Voltage V ........................... 4.5V to 16V IN SS/TRK 5 13 Output Voltage V ................... 0.8V to V -4V OUT IN Operating Temperature .............40 C to +85 C 12 FB 6 (3) Thermal Resistance COMP 7 11 JA JC 89 10 QFN20 (3mm x 4mm)............. 48...... 11... C/W PG BST VIN Notes: 1) Exceeding these ratings may damage the device. Part Number* Package 2) The device is not guaranteed to function outside of its operating conditions. MP38873DL 3mm x 4mm QFN20 3) Measured on JESD51-7, 4-layer PCB. Temperature Top Marking 40 C to +85C 38873 For Tape & Reel, add suffix Z (e.g. MP38873DLZ) * For RoHS compliant packaging, add suffix LF (e.g. MP38873DLLFZ) ELECTRICAL CHARACTERISTICS V = 12V, T = +25 C, unless otherwise noted. IN A Parameters Symbol Condition Min Typ Max Units Feedback Voltage V 4.5V V 16V 0.794 0.810 0.826 V FB IN Feedback Current I V = 0.8V 10 nA FB FB (4) Switch On Resistance R 25 m DS(ON) Switch Leakage V = 0V, V = 0V 0.1 10 A EN SW (4) Current Limit 21 A Oscillator Frequency f V = 0.6V, SYNC = 5V 400 KHz SW FB IN Fold-back Frequency V = 0V 100 KHz FB Maximum Duty Cycle V = 0.6V 90 % FB (4) Minimum On Time t 100 ns ON Soft-Start Charging Current I V = 0V 8 A SS SS Maximum COMP Level V V = 0.6V 4.4 V COMP MAX FB Gain of Error Amplifier G V = 1.5V 2 mA/V EA COMP Error Amplifier Sink Current V = 1.5V 270 A COMP Error Amplifier Source Current V = 1.5V +270 A COMP Power Good Ramp Up Threshold 90 % Power Good Ramp Down Threshold 85 % MP38873 Rev. 0.9 www.MonolithicPower.com 2 9/17/2009 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. 2009 MPS. All Rights Reserved.