Maxim Driver Ensures Reliable In-Car Displays Even During Cold Crank
Maxim Integrated has launched the Max 25512, a four-channel automotive LED backlight driver with an integrated boost converter, designed to keep in-car displays fully bright even during cold crank conditions when the input voltage drops to as low as 3V.
This single-chip LED driver eliminates the need for an external mosfet and a current sense resistor, and it integrates I²C communications, which helps reduce costs and board space by up to 30%. The driver boasts four 120mA channels and operates at 2.2MHz, offering what the company claims is the highest efficiency in the industry.
Modern start-stop automotive systems are great for improving fuel economy, but they can struggle to maintain display brightness during engine restarts. For instance, display lights that come on when you enter the car can flicker or turn off completely during a cold crank because the battery is heavily taxed. The Max 25512, however, can function at 3V after startup without requiring an additional pre-boost converter, ensuring the display stays on consistently.
With a 91% efficiency at 2.2MHz, this LED driver can maintain full, constant brightness for in-car displays during cold crank and start-stop scenarios. It also provides diagnostic features like short to GND alerts for each current sink and individual PWM settings through the I²C interface to enhance safety and display quality.
By integrating the boost converter and current sense resistor, along with eliminating the need for an external mosfet, the driver simplifies the design of automotive displays. The additional I²C communication interface supports display settings, diagnostics, and a hybrid dimming function to reduce EMI and improve dimming ratios.
The device comes in a compact 24-pin, 4x4x0.75mm QFN package.
Sang Oh, a senior research analyst at Omdia, pointed out that the number of displays in automobiles is set to increase significantly over the next five years to support more functions and higher resolutions. Keeping these displays consistently bright and energy-efficient is crucial for automakers.
Szu-Kang Hsien, director of business management for Maxim’s automotive division, added that car manufacturers are looking for more integrated LED drivers to cut costs and save PCB space. The Max 25512 meets these demands with its high level of integration and efficiency at a 2.2MHz switching frequency.
