EVALUATION KIT AVAILABLE MAX17504 4.5V60V, 3.5A, High-Efficiency, Synchronous Step-Down DC-DC Converter with Internal Compensation General Description Benefits and Features The MAX17504/MAX17504S high-efficiency, high- Eliminates External Components and Reduces Total Cost voltage, synchronously rectified step-down converter with No Schottky-Synchronous Operation for High dual integrated MOSFETs operates over a 4.5V to 60V Efficiency and Reduced Cost input. It delivers up to 3.5A and 0.9V to 90% V output Internal compensation for Stable Operation at Any IN voltage. Built-in compensation across the output voltage Output Voltage range eliminates the need for external components. The All Ceramic Capacitor Solution: Ultra-Compact feedback (FB) regulation accuracy over -40C to +125C Layout with as Few as Eight External Components is 1.1%. The device is available in a compact (5mm x Reduce Number of DC-DC Regulators to Stock 5mm) TQFN lead (Pb)-free package with an exposed pad. Wide 4.5V to 60V Input Voltage Range Simulation models are available. 0.9V to 90% V Output Voltage IN Delivers Up to 3.5A Over Temperature The device features a peak-current-mode control 100kHz to 2.2MHz Adjustable Frequency with architecture with a MODE feature that can be used to External Synchronization operate the device in pulse-width modulation (PWM), MAX17504S Allows Higher Frequency Of Operation pulse-frequency modulation (PFM), or discontinuous Available in a 20-Pin, 5mm x 5mm TQFN Package mode (DCM) control schemes. PWM operation provides Reduce Power Dissipation constant frequency operation at all loads, and is useful Peak Efficiency > 90% in applications sensitive to switching frequency. PFM PFM and DCM Modes for High Light-Load Efficiency operation disables negative inductor current and Shutdown Current = 2.8FA (typ) additionally skips pulses at light loads for high efficiency. Operate Reliably DCM features constant frequency operation down to Hiccup-Mode Current Limit and Autoretry Startup lighter loads than PFM mode, by not skipping pulses, Built-In Output Voltage Monitoring(Open-Drain but only disabling negative inductor current at light loads. RESET Pin) DCM operation offers efficiency performance that lies Resistor Programmable EN/UVLO Threshold between PWM and PFM modes. The MAX17504S offers Adjustable Soft-Start and Pre-Biased Power-Up a lower minimum on-time that allows for higher switching High Industrial -40C to +125C Ambient Operating frequencies and a smaller solution size. Temperature Range/-40C to +150C Junction A programmable soft-start feature allows users to reduce Temperature Range input inrush current. The device also incorporates an output enable/undervoltage lockout pin (EN/UVLO) that allows the user to turn on the part at the desired input- voltage level. An open-drain RESET pin provides a Ordering Information appears at end of data sheet. delayed power-good signal to the sys tem upon achieving successful regulation of the output voltage. Applications Industrial Power Supplies Distributed Supply Regulati on Base Station Power Supplie s Wall Transformer Regulatio n High -Voltage Single-Board Systems General-Purpose Point-of-L oad 19-6844 Rev 3 5/17MAX17504 4.5V60V, 3.5A, High-Efficiency, Synchronous Step-Down DC-DC Converter with Internal Compensation Absolute Maximum Ratings (Note 1) V to PGND .........................................................-0.3V to +65V SGND to PGND.................................................... -0.3V to +0.3V IN EN/UVLO to SGND ...............................................-0.3V to +65V LX Total RMS Current ........................................................5.6A LX to PGND................................................-0.3V to (V + 0.3V) Output Short-Circuit Duration ....................................Continuous IN BST to PGND ........................................................-0.3V to +70V Continuous Power Dissipation (T = +70C) (multilayer board) A BST to LX .............................................................-0.3V to +6.5V TQFN (derate 33.3mW/C above T = +70C) ......2666.7mW A BST to V ...........................................................-0.3V to +65V Junction Tempera ture ......................................................+150C CC FB, CF, RESET, SS, MODE, SYNC, Storage Tempera ture Range ............................ -65NC to +160C RT to SGND .....................................................-0.3V to +6.5V Lead Temperature (soldering, 10s) .................................+300C V to SGND .......................................................-0.3V to +6.5V Soldering Temperature (reflow) .......................................+260C CC 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. Package Information PACKAGE TYPE: 20 TQFN Package Code T2055+4 Outline Number 21-0140 Land Pattern Number 90-0009 THERMAL RESISTANCE, FOUR-LAYER BOARD Junction to Ambient ( ) 30C/W JA Junction to Case ( ) 2C/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. Note 1: Junction temperature greater than +125C degrades operating lifetimes. Electrical Characteristics (V = V = 24V, R = 40.2kI (500kHz), C = 2.2F, V = V = V = V = 0V, LX = SS = RESET = IN EN/UVLO RT VCC PGND SGND MODE SYNC open, V to V = 5V, V = 1V, T = -40C to +125C, unless otherwise noted. Typical values are at T = +25C. All voltages are BST LX FB A A referenced to SGND, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS INPUT SUPPLY (V ) IN Input Voltage Range V 4.5 60 V IN Input Shutdown Current I V = 0V (shutdown mode) 2.8 4.5 IN-SH EN/UVLO V = 1V, MODE = RT= open 118 A FB I Q PFM V = 1V, MODE = open 162 FB Input Quiescent Current I DCM mode, V = 0.1V 1.16 1.8 Q DCM LX mA Normal switching mode, f = 500kHz, SW I 9.5 Q PWM V = 0.8V FB www.maximintegrated.com Maxim Integrated 2