I have been trying to use the USB2244 on a board but i can't seem to get it working and I am not sure what the problem is. I have went over and over the datasheet but can't seem to figure out what i'm missing . I have attached my schematics, I have verified i have 3.3V, and also that the 1.8 Rails are both being generated internally, i do have a 24MHz clock as well.



when i insert a MicroSD card i see the CD line go low BUT the CRD_PWR is never supplied. and USB2244 is connected to system ,usb port not detected.



I can't figure out what i could be missing ?

 

What is the voltage on the reset pin? R4 and R6 work out to 25 uA and it lists a possible leakage of 10 uA is why I'm asking. It doesn't seem logical as the datasheet says the clock is supposed to turn off on reset. I am wondering if there is an intermittent sag in the reset line that is causing the issue... just because I have seen it happen with a PIC before.

 

What is the voltage on the reset pin? R4 and R6 work out to 25 uA and it lists a possible leakage of 10 uA is why I'm asking. It doesn't seem logical as the datasheet says the clock is supposed to turn off on reset. I am wondering if there is an intermittent sag in the reset line that is causing the issue... just because I have seen it happen with a PIC before.

VBUS input voltage is 5v. so i am using voltage divider R4=100k ,R5=100k,output voltage 2.5v . i think this voltage is enough for reset pin. this functionally described as a reference circuit and also i connected the external reset switch but its not working. i attached the refence circuit.

 

VBUS input voltage is 5v. so i am using voltage divider R4=100k ,R5=100k,output voltage 2.5v . i think this voltage is enough for reset pin. this functionally described as a reference circuit and also i connected the external reset switch but its not working. i attached the refence circuit.

I didn't realize you were working with an evaluation board. I would assume all the values are correct then. I have in the past had strange behavior as a result to too high of a resistance on reset pin pull ups and thought maybe this was your case.

 

hi ,currently usb port detected ,but can't sd card access. Card power pin not generating 3.3v and usb2244 ic over heating.I can't figure out what i could be missing ?