MAX17550 60V, 25mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter with 22A No-Load Supply Current General Description Benefits and Features The MAX17550 high-efficiency, high-voltage, synchronous Reduces External Components and Total Cost step-down DC-DC converter with integrated MOSFETs No SchottkySynchronous operates over a 4V to 60V input. The converter can deliver Internal Compensation for Any Output Voltage Built-In Soft-Start up to 25mA and generates output voltages from 0.8V up to 0.9 x V . The feedback (FB) voltage is accurate to All-Ceramic Capacitors, Compact Layout IN within 1.75% over -40C to +125C. Reduces Number of DC-DC Regulators to Stock The MAX17550 uses peak-current-mode control. The Wide 4V to 60V Input device can be operated in pulse-width modulation (PWM) Adjustable 0.8V to 0.9 x V Output IN or pulse-frequency modulation (PFM) modes. 100kHz to 2.2MHz Adjustable Switching Frequency with External Synchronization The device is available in a 10-pin (3mm x 2mm) TDFN and 10-pin (3mm x 3mm) MAX packages. Simulation Reduces Power Dissipation models are available. 22A Quiescent Current Peak Efficiency > 90% Applications PFM Enables Enhanced Light-Load Efficiency 1.2A Shutdown Current Industrial sensors and Process control High-Voltage LDO Replacement Operates Reliable in Adverse Environments Battery-Powered Equipment Peak Current-Limit Protection HVAC and Building Control Built-In Output-Voltage Monitoring RESET Programmable EN/UVLO Threshold Ordering Information appears at end of data sheet. Monotonic Startup Into Prebiased Load Overtemperature Protection MAX is a registered trademark of Maxim Integrated Products, Inc. -40C to +125C Operation Typical Application CircuitsHigh-Efficiency 5V, 25mA Regulator L1 V V IN OUT 1mH 6V TO 60V 5V, 25mA IN LX C IN C MAX17550 OUT 1F 10F EN/UVLO GND R4 SS 22.1 V OUT C1 R1 0.22F MODE 261k FB RT/SYNC R2 49.9k SWITCHING FREQUENCY = 220kHz R3 L1 COILCRAFT LPS5030-105M 191k C MURATA 10F/X7R/6.3V/0805 (GRM21BR70J106K) RESET OUT C MURATA 1F/X7R/100V/1206 (GRM31CR72A105K) IN 19-7109 Rev 1 3/15MAX17550 60V, 25mA, Ultra-Small, High-Efficiency Synchronous Step-Down DC-DC Converter with 22A No-Load Supply Current Absolute Maximum Ratings IN, EN/UVLO, V , RESET to GND.....................-0.3V to 70V Operating Temperature Range ......................... -40C to +125C OUT LX to GND ......................................................-0.3V to IN + 0.3V Junction Temperature ......................................................+150C RT/SYNC, SS, FB, MODE to GND ...........................-0.3V to 6V Storage Temperature Range ............................ -65C to +150C LX Total RMS Current ........................................................0.8A Lead Temperature (soldering, 10s) .................................+300C Output Short-Circuit Duration ....................................Continuous Soldering Temperature (reflow) .......................................+260C Continuous Power Dissipation (T = +70C) A TDFN (derate 14.9mW/C above +70C) ..............1188.7mW MAX (derate 8.8mW/C above +70C) ..................707.3mW Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. (Note 1) Package Thermal Characteristics TDFN MAX Junction-to-Ambient Thermal Resistance ( ) .......67.3C/W Junction-to-Ambient Thermal Resistance ( ) .....113.1C/W JA JA Junction-to-Case Thermal Resistance ( ) ............18.2C/W Junction-to-Case Thermal Resistance ( ) ...............42C/W JC JC Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial. Electrical Characteristics (V = 24V, V = 0V, V = 3.3V, V = 0.85V, V = 1.5V, RT/SYNC = 191k, LX = SS = MODE = RESET = unconnected IN GND OUT FB EN/UVLO T = T = -40C to +125C, unless otherwise noted. Typical values are at T = +25C. All voltages are referenced to GND, unless A J A otherwise noted.) (Note 3) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS INPUT SUPPLY (IN) Input Voltage Range V 4 60 V IN Input Shutdown Current I V = 0V, T = +25C 0.67 1.2 2.25 IN-SH EN/UVLO A I V = unconnected (Note 2) 18 32 A Q-PFM MODE Input Supply Current I Normal switching mode, V = 24V 180 485 650 Q-PWM IN EXTERNAL BIAS (V ) OUT V Switchover Threshold 2.96 3.05 3.12 V OUT ENABLE/UVLO (EN/UVLO) V V rising 1.2 1.25 1.3 ENR EN/UVLO EN/UVLO Threshold V V falling 1.1 1.15 1.2 V ENF EN/UVLO V V falling, true shutdown 0.7 EN-TRUESD EN/UVLO EN/UVLO Leakage Current I V = 1.3V, T = +25C -100 +100 nA EN EN/UVLO A POWER MOSFETs High-Side pMOS On-Resistance R I = 0.1A (sourcing) 3.2 5.9 11.1 DS-ONH LX Low-Side nMOS On-Resistance R I = 0.1A (sinking) 1.6 3.0 6 DS-ONL LX V = 0V, T = +25C, EN A LX Leakage Current I -1 +1 A LX-LKG V = (V + 1V) to (V - 1V) LX GND IN Maxim Integrated 2 www.maximintegrated.com