General Description

The MAX16935/MAX16939 are 3.5A current-mode stepdown converters with integrated high-side and low side MOSFETs designed to operate with an external Schottky diode for better efficiency. The low-side MOSFET enables fixed-frequency forced-PWM (FPWM) operation under light-load applications. The devices operate with input voltages from 3.5V to 36V, while using only 28FA quiescent current at no load. The switching frequency is resistor programmable from 220kHz to 2.2MHz and can be synchronized to an external clock. The devices’ output voltage is available as 3.3V/5V fixed or adjustable from 1V to 10V. The wide input voltage range along with its ability to operate at 98 duty cycle during undervoltage transients make the devices ideal for automotive and industrial applications.

Benefits and Features

● Integration and High-Switching Frequency Saves Space

    • Integrated 3.5A High-Side Switch

    • Low-BOM-Count Current-Mode Control Architecture

    • Fixed Output Voltage with ±2 Accuracy or Externally Resistor Adjustable (1V to 10V)

    • 220kHz to 2.2MHz Switching Frequency with Three Operation Modes (Skip Mode, Forced Fixed-Frequency Operation, and External Frequency Synchronization)

    • Automatic LX Slew-Rate Adjustment for Optimum Efficiency Across Operating Frequency Range

● 180° Out-of-Phase Clock Output at SYNCOUT Enables Cascaded Power Supplies for Increased Power Output

● Spread-Spectrum Frequency Modulation Reduces EMI Emissions

● Wide Input Voltage Range Supports Automotive Applications

    • 3.5V to 36V Input Voltage Range (42V Tolerant)

    • Enable Input Compatible from 3.3V Logic Level to 42V

● Robust Performance Supports Wide Range of Automotive Applications

    • -40°C to +125°C Automotive Temperature Range

    • Thermal-Shutdown Protection

    • AEC-Q100 Qualified

● Power-Good Output Allows Power-Supply Sequencing

● Tight Overvoltage Protection Provides Smaller Overshoot Voltages (MAX16939)

Applications

● Point-of-Load Applications

● Distributed DC Power Systems

● Navigation and Radio Head Units