4.5V to 42V Input, Ultra-Small, High-Efficiency, Iso-Buck DC-DC Converter

The MAX17682 is a high-voltage, high-efficiency, iso-buck DC-DC converter designed to provide isolated power up to 10W. The device operates over a wide 4.5V to 42V input voltage range and uses primary-side feedback to regulate the output voltage. It delivers primary peak current up to 3.7A and regulates primary output voltage to within ±1.2% over -40°C to +125°C.

The device features peak-current-mode control with pulse-width modulation (PWM) scheme. The low-resistance, on-chip MOSFETs ensure high efficiency at full load and simplify the layout.

A programmable soft-start feature allows users to reduce 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 inputvoltage level. An open-drain, active-low RESETB pin provides a delayed power-good signal to the system upon achieving successful regulation of the primary output voltage.

The device operates over the -40°C to +125°C industrial temperature range and is available in a compact 20-pin (4mm x 4mm) TQFN package. Simulation models are available.

Applications

* Communication Hub in Smart Meters * Floating Power Supply Generation * Industrial Process Control * Isolated Power Supplies in Medical Equipment

* Eliminates External Components and Reduces Total Cost

* Synchronous Primary Operation for High Efficiency and Reduced Cost

* All-Ceramic Capacitors, Ultra-Compact Layout

* Reduces Number of DC-DC Regulators to Stock

* Wide 4.5V to 42V Input Voltage Range

* 0.9V to 92% VIN Primary Output Voltage

* Delivers up to 3.7A Peak Current

* 100kHz to 500kHz Adjustable Frequency with External Synchronization

* Available in a 20-Pin, 4mm x 4mm TQFN Package

* Reduces Power Dissipation

* Peak Efficiency > 90%

* Shutdown Current = 2.8µA (typ)

* Operates Reliably in Adverse Industrial Environments

* Hiccup-Mode Current Limit, Sink Current Limit, and Auto-Retry Startup

* Programmable EN/UVLO Threshold

* Adjustable Soft-Start

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

* -40°C to +150°C Junction Temperature Range