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