topic Re: LPC1778FET208 GPIO Current Output in LPC Microcontrollers

LPC1778FET208 GPIO Current Output

VMS — Wed, 21 Oct 2020 10:56:21 GMT

Hi,

How much current we can draw from GPIO port pins in LPC1778FET208.

Re: LPC1778FET208 GPIO Current Output

xiangjun_rong — Wed, 21 Oct 2020 13:53:28 GMT

Hi, Friend,

Pls refer to Table 13. Static characteristics … in data sheet of LPC177x, both the source/sink current is 4mA.

Hope it can help you

XiangJun Rong

Re: LPC1778FET208 GPIO Current Output

VMS — Wed, 21 Oct 2020 14:13:54 GMT

Hi Xiangjun,

Thanks for your kind reply, in datasheet it is mentioned only minimum current this means we can able to draw 4mA maximum.

Re: LPC1778FET208 GPIO Current Output

xiangjun_rong — Fri, 23 Oct 2020 07:08:26 GMT

Hi, Venkatesh,

The source current means the GPIO outputting current when the GPIO pin outputs logic high, the higher the source current is, the higher voltage drop is. The 4mA current means that we can guarantee that the voltage drop is less than 400mV when the source current is 4mA.

I copy the Fig from the data sheet of LPC177x. which can be downloaded from the link:

https://www.nxp.com.cn/docs/en/data-sheet/LPC178X_7X.pdf

The sink current is the current the pin draws when the GPIO pin outputs LOW logic. The higher the sink current is, the higher the GPIO pin voltage is. The 4mA sink current means that we can guarantee the pin voltage rising is less than 400mV when the pin draws 4mA current.

Hope it can help you