MAX20078 Synchronous Buck, High-Brightness LED Controller

Product Details

The MAX20078 is a high-voltage, synchronous n-channel MOSFET controller for high-current buck LED drivers. The device uses a proprietary average current-mode-control scheme to regulate the inductor current. This control method does not need any control-loop compensation while maintaining nearly constant switching frequency. Inductor current sense is achieved by sensing the current in the bottom synchronous n-channel MOSFET. It does not require any current sense at high voltages. The device operates over a wide 4.5V to 65V input range. The device is designed for high-frequency operation and can operate at switching frequencies as high as 1MHz. The high- and low-side gate drivers have peak source and sink current capability of 2A. The driver block also includes a logic circuit that provides an adaptive nonoverlap time to prevent shoot-through currents during transition. The device includes both analog and PWM dimming. The device includes a 5V VCC regulator capable of delivering 10mA to external circuitry. The device also includes a current monitor that provides an analog voltage proportional to the inductor current. The device has a fault flag that indicates open and shorts across the output. Protection features include inductor current-limit protection, overvoltage protection, and thermal shutdown. The MAX20078 is available in a space-saving (3mm × 3mm), 16-pin TQFN or a 16-pin TSSOP package and is specified to operate over the -40°C to +125°C automotive temperature range.

Applications

  • Automotive Front Lights
  • Automotive Matrix Lights
  • Constant-Current Regulators
  • Head-Up Displays


Features and Benefits

  • Automotive Ready: AEC-Q100 Qualified
  • Wide Input Voltage Range: 4.5V to 65V
  • Easy to Design
    • No Compensation Components
    • Programmable Switching Frequency
  • Wide Dimming Ratio Allows High Contrast Ratio
    • Analog Dimming
    • PWM Dimming
  • Suitable for Matrix Lighting
    • Maintains Current Regulation While Shorting/Opening Individual LEDs in the String
    • Ultra-Fast Response Control Loop Prevents Overshoots and Undershoots
  • Fault Detection and Protection
    • Overvoltage Protection
    • Open and Short Detection
    • Thermal Shutdown
    • Inductor Current Monitor
  • Low-Power Shutdown Mode