4.5V–42V, 1.7A, High-Efficiency, Synchronous Step-Down DC-DC Converter With Internal Compensation

The MAX17545 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 1.7A and generates output voltages from 0.9V up to 0.9 x VIN. The feedback (FB) voltage is accurate to within ±1.1% over -40°C to +125°C.

The MAX17545 uses peak-current-mode control. The device can be operated in pulse-width modulation (PWM), pulse-frequency modulation (PFM), or discontinuous conduction mode (DCM) control schemes.

The device is available in a 20-pin (4mm × 4mm) TQFN package. Simulation models are available.

Applications

* Base Station Power Supply * Distributed Supply Regulation * General-Purpose Point-of-Load * High-Voltage Single-Board Systems * Industrial Power Supplies

* Reduces External Components and Total Cost

* No Schottky—Synchronous Operation

* Internal Compensation for Any Output Voltage

* Built-In Soft-Start

* All-Ceramic Capacitors, Compact Layout

* Reduces Number of DC-DC Regulators to Stock

* Wide 4.5V to 42V Input

* Adjustable 0.9V to 0.9 x VIN Output

* 100kHz to 2.2MHz Adjustable Switching Frequency with External Synchronization

* Reduces Power Dissipation

* Peak Efficiency > 90%

* PFM/DCM Enables Enhanced Light-load Efficiency

* 2.8µA Shutdown Current

* Operates Reliably in Adverse Industrial Environments

* Peak Current-Limit Protection

* Built-in Output Voltage Monitoring with Active-Low RESET

* Programmable EN/UVLO Threshold

* Monotonic Startup into Prebiased Load

* Overtemperature Protection

* High Industrial -40°C to +125°C Ambient Operating Temperature Range/-40°C to +150°C Junction Temperature Range