Can anyone help me to find out the limits of NXP LPC1114 GPIO current sink and source capabilities?
After reading the manual and the product datasheet I could not find this information anywhere. Also searching on Google I could not find anything.
All I could find is information about the high current sink capabilities of I2C pins.
The info you want is on Table 16 on the LPC111X datasheet. It depends on whether you're using a "Standard Port Pin", which allows a handful of mA, or a "High Drive Output Pin", which allows about 12 mA, all dependent on Vdd levels.