MAX17541G 42V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter
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42V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter General Description The MAX17541G high-efficiency, high-voltage, synchronous step-down DC-DC converter with integrated MOSFETs operates over 4.5V to 42V input. The converter can deliver up to 500mA and generates output voltages from 0.9V up to 0.92 x VIN. The feedback (FB) voltage is accurate to within ±1.7% over -40°C to +125°C. The MAX17541G uses peak-current-mode control with pulse-width modulation (PWM) and operates with fixed 600kHz switching frequency at any load. The device is available in a 10-pin (3mm x 2mm) TDFN package. Simulation models are available. Industrial Process Control HVAC and Building Control Base Station, VOIP, Telecom Home Theatre Battery-Powered Equipment General-Purpose Point of Load ● Reduces External Components and Total Cost • Schottky-Synchronous Operation No • All-Ceramic Capacitors, Ultra-Compact Layout ● Reduces Number of DC-DC Regulators to Stock • Wide 4.5V to 42V Input • Adjustable 0.9V to 92%VIN Output • Delivers up to 500mA ● Reduces Power Dissipation • Peak Efficiency > 90% • Shutdown Current = 0.9μA (typ) ● Operates Reliably in Adverse Industrial Environments • Hiccup-Mode Current Limit, Sink Current Limit, and Autoretry Startup • Built-In Output-Voltage Monitoring (RESET Pin) • Programmable EN/UVLO Threshold • Adjustable Soft-Start and Prebiased Power-Up • -40°C to +125°C Operation Ordering Information appears at end of data sheet. MAX17541G Application Circuit (5V Output, 500mA Maximum Load Current) VIN

42V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter 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 Thermal Characteristics (Note 1) 10 TDFN Continuous Power Dissipation (TA = +70°C) (derate 14.9mW/°C above +70°C)...

42V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter Electrical Characteristics (continued) (VIN = 24V, VGND = VPGND = 0V, CVIN = 1μF, CVCC = 1μF, VEN = 1.5V, CSS = 3300pF, VFB = 0.98 x VOUT, LX = unconnected, RESET = unconnected. TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) (Note 2) PARAMETER High-Side pMOS On-Resistance Low-Side nMOS On-Resistance SOFT-START (SS) Charging Current FEEDBACK (FB/VO) FB Regulation Voltage FB Input Bias Current OUTPUT VOLTAGE (VOUT)...

42V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter Electrical Characteristics (continued) (VIN = 24V, VGND = VPGND = 0V, CVIN = 1μF, CVCC = 1μF, VEN = 1.5V, CSS = 3300pF, VFB = 0.98 x VOUT, LX = unconnected, RESET = unconnected. TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) (Note 2) PARAMETER RESET RESET Output Level Low RESET Output Leakage Current High VOUT Threshold for RESET Falling VOUT Threshold for RESET Rising RESET Delay After FB Reaches 95% Regulation...

42V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter Typical Operating Characteristics (VIN = 24V, VGND = VPGND = 0V, CVIN = 1μF, CVCC = 1μF, VEN = 1.5V, CSS = 3300pF, VFB = 0.98 x VOUT, LX = unconnected, RESET = unconnected, TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT FIGURE 5 CIRCUIT 5V OUTPUT EFFICIENCY vs. LOAD CURRENT FIGURE 6 CIRCUIT EN/UVLO THRESHOLD VOLTAGE (V) EN/UVLO THRESHOLD vs. TEMPERATURE RISING THRESHOLD...

42V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter Typical Operating Characteristics (continued) (VIN = 24V, VGND = VPGND = 0V, CVIN = 1μF, CVCC = 1μF, VEN = 1.5V, CSS = 3300pF, VFB = 0.98 x VOUT, LX = unconnected, RESET = unconnected, TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) SOFT-START/SHUTDOWN FROM EN/UVLO, 5V OUTPUT, 0.5A LOAD CURRENT, FIGURE 6 CIRCUIT TOC11 RUNAWAY CURRENT LIMIT SOFT-START/SHUTDOWN FROM EN/UVLO, 3.3V OUTPUT, 0.5A LOAD CURRENT, FIGURE 5...

42V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter Typical Operating Characteristics (continued) (VIN = 24V, VGND = VPGND = 0V, CVIN = 1μF, CVCC = 1μF, VEN = 1.5V, CSS = 3300pF, VFB = 0.98 x VOUT, LX = unconnected, RESET = unconnected, TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) 5V OUTPUT, FIGURE 6 CIRCUIT (LOAD CURRENT STEPPED FROM 0.25A TO 0.5A) TOC17 3.3V OUTPUT, FIGURE 5 CIRCUIT (LOAD CURRENT STEPPED FROM 0.25A TO 0.5A) TOC16 STEADY-STATE SWITCHING...

42V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter Pin Configurations TOP VIEW MAX17541G PGND TDFN (3mm x 2mm) *EP = EXPOSED PAD. CONNECT TO GND Power Ground. Connect PGND externally to the power ground plane. Connect GND and PGND pins together at the ground return path of the VCC bypass capacitor. Feedback Input. Connect FB to the center of the resistive divider between VOUT and GND. Soft-Start Input. Connect a capacitor from SS to GND to set the soft-start time. External Loop Compensation. Connect an RC network from COMP to GND. See External Loop Compensation...

42V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter P DRIVER VIN CURRENT SENSE VCC COMP HICCUP SLOPE COMPENSATION START REFERENCE SWITCHOVER LOGIC