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ROHM Semiconductor BD18398A Current LED Drivers
ROHM Semiconductor BD18398A Current LED Drivers are 2-ch/3-ch synchronous buck DC-DC LED drivers using on-time topology. These drivers support a near-fixed switching frequency and fast regulation of the switching duty cycle. These devices use an average LED-current feedback buck topology to achieve more accurate LED-current regulation across a wide input-to-LED output range. The BD18398A supports individual 10-bit analog dimming and 10-bit PWM dimming for LED current by programming the 10-bit register via SPI. The ROHM Semiconductor BD18398A will enter LIMP-HOME mode if SPI communication fails. In the LIMPHOME mode, individual LED currents can be set via the external pins and maintained when input power is applied, without SPI communication.