LPC MicrocontrollersのトピックRe: Driving a 0603 LED by LPC5516

Driving a 0603 LED by LPC5516

uzslm — Sun, 15 Dec 2024 08:57:58 GMT

As a general practice on STM32 or PIC18,Is that possible to drive a green or red LED by GPIO from LPC5516, plus a resistor on the IO pin?

Re: Driving a 0603 LED by LPC5516

xiangjun_rong — Mon, 16 Dec 2024 01:53:12 GMT

Hi,

It is dependent on the current the LED has to consume to light up the LED.

The GPIO pin of LPC5516 can provide 4mA current, if 4mA current can light up the LED, it is okay, you can connect a serial resistor (3.3V-0.7V)/4mA=650 ohm to limit the current.

If the 4mA is not enough to light up the LED, pls connect a transistor.

copied from data sheet of LPC551x.

AS the above table, both the source/sink current of each GPIO is 4mA.

Hope it can help you

XiangJun Rong

Re: Driving a 0603 LED by LPC5516

uzslm — Tue, 17 Dec 2024 00:59:01 GMT

XiangJun,

Thank you for all the information!

I had similar LEDs as indicators working on my previous boards,i would like to check their current to decide how muck ohms for the resistors,hope that 1k can be okay.

Kind Regards,

uzslm