MP2355 3A, 23V, 380KHz Step-Down Converter The Future of Analog IC Technology DESCRIPTION FEATURES The MP2355 is a step-down regulator with a Programmable Soft-Start built in internal Power MOSFET. It achieves 3A 100m Internal Power MOSFET Switch continuous output current over a wide input Stable with Low ESR Output Ceramic supply range with excellent load and line Capacitors regulation. Up to 95% Efficiency 20 A Shutdown Mode Current mode operation provides fast transient 3A Output Current response and eases loop stabilization. Fault Wide 4.75V to 23V Operating Input Range condition protection includes cycle-by-cycle current limiting and thermal shutdown. Adjustable Fixed 380KHz Frequency soft-start reduces the stress on the input source Thermal Shutdown at turn-on. In shutdown mode the regulator draws Cycle-by-Cycle Over Current Protection 20A of supply current. Under Voltage Lockout The MP2355 uses a minimum number of APPLICATIONS readily available external components to Distributed Power Systems complete a 3A step-down DC to DC converter Battery Chargers solution. Pre-Regulator for Linear Regulators EVALUATION BOARD REFERENCE MPS and The Future of Analog IC Technology are Registered Trademarks of Board Number Dimensions Monolithic Power Systems, Inc. EV2355DN-00A 2.0X x 1.3Y x 0.5Z TYPICAL APPLICATION Efficiency vs INPUT Load Current 4.75V to 23V 10nF 95 V =5.0V OUT 90 32 VIN BST 85 OPEN 8 4 OUTPUT AUTOMATIC RUN LX 3.3V / 3A D1 STARTUP 80 MP2355 V =3.3V V =2.5V B330A OUT OUT 1 6 SS FB 75 GND COMP 70 5 7 4.7nF 10nF 65 60 0 500 1000 1500 2000 2500 3000 3500 LOAD CURRENT (mA) MP2355 TAC S01 MP2355 EC01 MP2355 Rev. 1.5 www.MonolithicPower.com 1 9/21/2007 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. 2007 MPS. All Rights Reserved. EFFICIENCY (%)MP2355 3A, 23V, 380KHz STEP-DOWN CONVERTER (1) PACKAGE REFERENCE ABSOLUTE MAXIMUM RATINGS Supply Voltage V .......................0.3V to +25V IN Switch Voltage V .......................0.3V to +26V LX TOP VIEW Boost Voltage V ..........V 0.3V to V + 6V BST LX LX All Other Pins.................................0.3V to +6V SS 1 8 RUN Junction Temperature...............................150C BST 2 7 COMP Lead Temperature ....................................260C VIN 3 6 FB Storage Temperature .............65C to +150 C LX 4 5 GND (2) Recommended Operating Conditions MP2355 PD01-SOIC8N Input Voltage V ............................ 4.75V to 23V EXPOSED PAD IN ON BACKSIDE Operating Temperature .............40 C to +85 C CONNECT TO PIN 5 (3) Thermal Resistance JA JC SOIC8N .................................. 50...... 10... C/W Part Number* Package Temperature Notes: SOIC8N MP2355DN 40 C to +85C 1) Exceeding these ratings may damage the device. (Exposed Pad) 2) The device is not guaranteed to function outside of its operating conditions. For Tape & Reel, add suffix Z (eg. MP2355DNZ) * 3) Measured on approximately 1 square of 1 oz copper. For RoHS compliant packaging, add suffix LF (eg. MP2355DN LFZ) ELECTRICAL CHARACTERISTICS V = 12V, T = +25 C, unless otherwise noted. IN A Parameter Symbol Condition Min Typ Max Units Shutdown Supply Current V = 0V 20 30 A RUN Supply Current V = 2.8, V = 1.5V 1.0 1.2 mA RUN FB 4.75V V 23V, IN Feedback Voltage V 1.194 1.222 1.250 V FB V < 2V COMP Error Amplifier Voltage Gain A 400 V/V VEA Error Amplifier G I = 10A 500 800 1120 A/V EA COMP Transconductance High-Side Switch-On R 95 m DS(ON)1 Resistance Low-Side Switch-On R 10 DS(ON)2 Resistance High-Side Switch Leakage V = 0V, V = 0V 0 10 A RUN LX Current (4) Current Limit 3.7 4.3 A Current Sense to COMP G 3.8 A/V CS Transconductance Oscillation Frequency f 330 380 430 KHz S Short Circuit Oscillation V = 0V 20 35 50 KHz FB Frequency Maximum Duty Cycle D V = 1.0V 90 % MAX FB Minimum Duty Cycle D V = 1.5V 0 % MIN FB EN Shutdown Threshold 0.9 1.2 1.5 V Voltage MP2355 Rev. 1.5 www.MonolithicPower.com 2 9/21/2007 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. 2007 MPS. All Rights Reserved.