USB Hud Design

Hi,
I am using an USB Hub in my PCB design. The Hub requires 3.3V & 1.2V power supplies, a reset & a 24MHz clock. I have given powers & reset to the IC. I am using an external crystal as the Hub has an internal crystal driver circuit. The powers & reset are proper but I am not getting the clock. Is the clock expected now or any other configurations needs to be done? The IC also has a PLLFILT (Phase Locked Loop filter capacitor) pin where an output voltage of 1.8V will come if the internal PLL circuit is configured. I am not getting this output also. Waiting for any kind of help...

With Regards,
Madhusoodana Bairy

We are going to need at least a schematic posted to look at what you have built, what components you are using, then we can help?

Hi, I cant disclose the schematics as our customer wants likes that, but I can tell the components I am using. I am using an HSIC USB Hub & a crystal as clock source.

Although we could certainly help you resolve this issue for your client we cannot without seeing the schematics, best of luck.

One thought, send me a complete list of parts you are using?

Ya, I can do that. Below are the parts i am using.

*Component* *Part Number*
Processor PCIMX6Q6AVT10AA
HSIC USB Hub USB4640-HZH-03
24MHz Crystal ABM8-24.000MHZ-R60-D-1-W-T
USB Power Switch MIC2026-1YM

Please send me at least a block diagram too

Hi, Got the permission from the management team. Schematics attached for your reference.

OK, great, we will take a look straight away

Seems to have section missing? Is there a page two?

Yes of-course! The Upstream port of the Hub connects to the processor & the downstream ports to connectors. But I do not have access to share those pages with you. I think this one page is enough for our discussion.

OK having reviewed the schematic we can see why this is not working for you, do you have a corporate email I can contact you?

Page 50 of the datasheet, C294 and C277.......
http://www.smsc.com/media/Downloads_Public/Data_Sheets/4640.pdf

Ya, it is mentioned as 18pF & me too used the same values...

Please direct message me with your contact email at Iwave Systems so we can take this further, thanks

We need to talk if you want to solve this.

Is the crystal quartz or ceramic?

Cap value is incorrect, if needed?

Crystal used is ceramic.
I did not understand your 2nd question.... Do you mean capacitor value I have used (18pF) is incorrect?

What is your email at iwave sustems and we can talk over there, you have more than one problem with your design / build

Sorry for late response, it is madhub(_at_)iwavesystems.com. But I think it is easier to discuss in this site itself ...