Dear
I am trying to find out how much an I/O pin of the MCU can source our sink.
I need to pull 4 enable pins of an ic high with 1mA with port 2 of the AT89C51CC03 that is powered on 3,3V (and voltage need to stay above 2V). But I am not sure how much the µC can source.
I was looking the the diagram below (page 168 -169 of datasheet) but I think I don't understand it correct.
I'm thinking that VOH means the following: If VCC is 3,3V and I make the pin high. Now I load the pin to the ground that there is a current of 60µA. The voltage on this pin now only will be 3,3-1,5 = 1,8V. Am I correct or where I'm I wrong?
I think I'm wrong because it has an internally pull up what I thought that was able to give much more current + 60µA is really not a lot. I was guessing more a value around 2 - 4 mA.
I hope somebody can explain my why I'm wrong and help me to understand
Kind regards
Stef
I am trying to find out how much an I/O pin of the MCU can source our sink.
I need to pull 4 enable pins of an ic high with 1mA with port 2 of the AT89C51CC03 that is powered on 3,3V (and voltage need to stay above 2V). But I am not sure how much the µC can source.
I was looking the the diagram below (page 168 -169 of datasheet) but I think I don't understand it correct.
I'm thinking that VOH means the following: If VCC is 3,3V and I make the pin high. Now I load the pin to the ground that there is a current of 60µA. The voltage on this pin now only will be 3,3-1,5 = 1,8V. Am I correct or where I'm I wrong?
I think I'm wrong because it has an internally pull up what I thought that was able to give much more current + 60µA is really not a lot. I was guessing more a value around 2 - 4 mA.
I hope somebody can explain my why I'm wrong and help me to understand
Kind regards
Stef