The current in each string can be programmed from 10mA to 30mA using an external resistor, which helps in setting the appropriate brightness level. Meanwhile, better than ±2% accurate current matching between strings ensures even LED brightness. The MAX17127 operates in a direct-dimming mode with a dimming frequency ranging from 100Hz to 25kHz. The LED current is directly controlled by the external dimming signal’s frequency and duty cycle. The wide dimming range eliminates the audible noise issues usually encountered in WLED drivers. A low feedback voltage at each LED string helps reduce power loss and improve efficiency.
The MAX17127 offers multiple features to protect the controller from faults, including overcurrent, overtemperature, and open-/short-string conditions. Additionally, the step-up controller has cycle-by-cycle current limiting and soft-start capability to control inrush current.