Linear Technology has a 60V, 1MHz step-down DC/DC converter which is designed to drive up to 30 LEDs in a display.
From a 48V input, the LT3596 can drive up to three strings of LEDs, each with up to ten 100mA LEDs in series, delivering efficiencies of over 90%.
The converter uses a single 800mA, 60V internal switch to provide a step-down constant current source. The internal buck converter uses an adaptive feedback loop to regulate the output voltage slightly higher than the required LED voltage to maintain efficiency.
The input voltage range of 6V to 60V is tuned for automotive and industrial applications.
There is also current matching for uniform display brightness and PWM dimming offers dimming ratios as high as 10,000:1.
A programmable 200kHz to 1MHz fixed frequency operation and current-mode architecture ensures stable operation over a wide range of supply and output voltages, minimising the size of external components.
The switching frequency cal also be synchronised to an external clock.
The LT3596EUHG is available in a 39-lead 5mm x 8mm QFN package.