MAX17531 4V to 42V, 50mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter with 22A No-Load Supply Current General Description Benefits and Features The MAX17531 high-efficiency, high-voltage, Reduces External Components and Total Cost synchronous step-down DC-DC converter with integrated No SchottkySynchronous MOSFETs operates over a 4V to 42V input. The converter Internal Compensation for Any Output Voltage Built-In Soft-Start can deliver up to 50mA and generates output voltages from 0.8V up to 0.9 x V . The feedback (FB) voltage is All-Ceramic Capacitors, Compact Layout IN accurate to within 1.75% over -40C to +125C. Reduces Number of DC-DC Regulators to Stock The MAX17531 uses peak-current-mode control and can Wide 4V to 42V Input be operated in pulse-width modulation (PWM) or pulse- Adjustable 0.8V up to 0.9 x V Output IN frequency modulation (PFM) modes. 100kHz to 2.2MHz Adjustable Switching Frequency with External Synchronization The device is available in 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 Reliably in Adverse Environments Battery-Powered Equipment Peak Current Limit Protection HVAC and Building Control Built-In Output Voltage Monitoring RESET Programmable EN/UVLO Threshold Monotonic Startup into Prebiased Load MAX is a registered trademark of Maxim Integrated Products, Inc. Overtemperature Protection Ordering Information appears at end of data sheet. High Industrial -40C to +125C Ambient Operating Temperature Range / -40C to +150C Junction Temperature Range Typical Application CircuitHigh-Efficiency 5V, 50mA Regulator L1 V V IN OUT 330H 6V TO 42V 5V IN LX MAX17531 C OUT C IN 10F 1F EN/UVLO GND R4 SS 22.1 V OUT C1 R1 0.22F MODE 261k FB RT/SYNC R2 SWITCHING FREQUENCY = 300kHz 49.9k L1: COILCRAFT LPS5030-334M R3 C : MURATA 10F/X7R/6.3V/0805 (GRM21BR70J106K) 140k OUT C : MURATA 1F/X7R/50V/0805 (GRM21BR71H105K) IN RESET 19-7423 Rev 2 8/17MAX17531 4V to 42V, 50mA, 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 48V Operating Temperature Range (Note 1) ........... -40C to +125C OUT LX to GND ....................................................-0.3V to V + 0.3V Junction Temperature ......................................................+150C IN Storage Temperature Range ............................ -65C to +150C RT/SYNC, SS, FB, MODE to GND ...........................-0.3V to 6V LX Total RMS Current ........................................................0.8A Lead Temperature (soldering, 10s) .................................+300C Soldering Temperature (reflow) .......................................+260C Output Short-Circuit Duration ....................................Continuous 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: Junction temperature greater than +125C degrades operating lifetimes. Package Information PACKAGE TYPE: 10 TDFN Package Code T1032N+1 Outline Number 21-0429 Land Pattern Number 90-0082 THERMAL RESISTANCE, FOUR-LAYER BOARD Junction to Ambient ( ) 67.3C/W JA Junction to Case ( ) 18.2C/W JC PACKAGE TYPE: 10 MAX Package Code U10+5 Outline Number 21-0061 Land Pattern Number 90-0330 THERMAL RESISTANCE, FOUR-LAYER BOARD Junction to Ambient ( ) 113.1C/W JA Junction to Case ( ) 42C/W JC For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a +, , or - in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. 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. Maxim Integrated 2 www.maximintegrated.com