One of the main challenges in driving a large number of LEDs in a multiplexed or Charlieplexed configuration is managing the refresh rate. The refresh rate refers to how many times per second each LED is updated during the scan cycle. In simpler terms, the refresh rate is directly proportional to the PWM frequency and inversely proportional to the number of scan lines. So, increasing the number of scan lines lowers the refresh rate unless the PWM frequency is also increased. To avoid flickering and ensure compatibility with high-speed cameras, the LED driver must support a refresh rate well above typical camera frame rates. The IS3xFL376x family addresses this by supporting PWM frequencies up to 312 kHz in 6+2-bit mode, which is more than sufficient for smooth, flicker-free performance. Another key consideration is power efficiency. Especially in battery-operated applications, keeping quiescent current low is critical. The IS3xFL376x family performs well here too, with a typical quiescent current under 0.28 mA when all LEDs are off, helping extend battery life and reduce heat.

Matrix array LED drivers are designed to manage a multitude of LEDs, more than possible with Multi Channel LED drivers. They achieve this by leveraging a matrix topology, where pins are allocated to rows and columns controlled by a scan timing architecture, enabling the management of a large array of LEDs. This approach reduces IC package pin count, simplifies PCB design, and enhances LED scalability.

This article introduces Lumissil's Microprocessor (MPU) portfolio: the X1600 family. This family utilizes XBurst 1, a 1GHz MIPS processor featuring an IEEE 754 compliant single/double precision FPU (floating point unit) and 32/64MB LPDDR2 (Low Power) and 128MB DDR2 options to support mobile power sensitive applications and performance applications. The X1600 is aimed at commercial, industrial white goods, IoT and general-purpose applications.