LED driver RGB and single-colour solid-state lighting

Diodes Incorporated has released its latest linear current LED driver, the DIODES AL5887. This product provides a simple way of driving numerous LEDs, allowing complex colour mixing and different lighting patterns. It integrates I2C and SPI interface options, providing maximum flexibility for system design. Delivering a broad colour range and an extensive dynamic range of brightness levels, this device may be employed in smart home appliances, EV charging stations, IoT information indicators, infotainment displays, and computing hardware.

The device has 36 independent programmable channels and can drive up to 12 RGB LED modules or 36 single-colour emitters. It provides an internal 12-bit PWM for colour and six-bit analog brightness control, which may be accessed via SPI or I2C interfacing.

There are three programmable banks for software control of every colour, making it simpler to program and set RGB lighting module patterns. Having an independent colour-mixing and brightness register per channel allows better colour-mixing schemes. The dimming function depends on a PWM duty cycle from 3% to 100%. Once the duty cycle goes below 3%, internal circuitry converts the output to analog dimming, maintaining linearity. By joining PWM and analog dimming functions, a dimming ratio greater than 100K to one can be achieved.

The device includes advanced diagnostics with fault-reporting functions. Its comprehensive set of built-in protection capabilities provides reliable operation and continued safety – including short-circuit and open-LED protection, and overtemperature shutdown. The pre-event overtemperature shutdown warning also results in early system protection.

Employing the two external hardware address pins, up to four devices can be connected in I2C mode. Including an internal 16MHz oscillator avoids the necessity for an external high-precision clock, decreasing the overall BOM cost.