ZHCSPI8D November 2021 – July 2022 TLC6984
PRODUCTION DATA
Decouple the VCC power supply voltage by placing a 0.1-μF ceramic capacitor close to VCC pin and GND plane. Depending on panel size, several electrolytic capacitors must be placed on the board equally distributed to get well regulated LED supply voltage VR/VG/VB. The ripple of the LED supply voltage must be less than 5% of their nominal value. Generally, the green and blue LEDs have the similar forward voltage and they can be supplied by the same power rail.
Furthermore, the VR > Vf(R) + 0.35 V (10-mA constant current example), the VG = VB > Vf(G/B) + 0.35 V (10-mA constant current example), here Vf(R), Vf(G/B) are representative for the maximum forward voltage of red, green/blue LEDs.
To simplify the power design, VCC can be connected to VR power rail.