[PCA9552] connecting multiple LED on 1 pin

[Kitta]

Hi,

I want to use 24 pcs of LED and make this synchronixed blink.

 In Application note "AN264.pdf" p24, it seems that I can connect multiple LED in one pin if I use external FET or a bipolar transistor. (each pin under 25mA, 100mA in total) I don't quite understand this FET or bipolar transistor connection.

Could you explain how I can do this? By doing so, would it be possible to control each LED individually? 

[JozefKozon · Accepted solution]

Hi Emiko,

each channel can be controlled individually. If you connect more LEDs to one channel, you will not be able to control each LED connected to this channel individually. 

JozefKozon_0-1720436116891.png

The LEDs above cannot be controlled individually. 

The LEDs below can be controlled individually.

JozefKozon_1-1720436182637.png

If you want to connect more LEDs to one channel, please use a bipolar transistor. 

JozefKozon_2-1720436281961.png

However we also have 24 channels LED controllers. E.g. PCA9956B with I2C interface or PCA9957HN with SPI interface. Please refer to this link for our LED controllers portfolio. 

JozefKozon_3-1720436470018.png

With Best Regards,

Jozef