TUSB9261: My customer use TUSB9261 for USB2.0 to SATA HDD,could you pls help review the SCH.Thanks.

Hi Jon,

Just to confirm, is your customer using an oscillator or a crystal? Depending on which, the configuration changes, so I would like to double check for feedback.

Please this is configured to match the recommended reset duration:

USB_VBUS should be routed to VBUS of the USB connector, not just a 3.3V rail. R10 should also be 90.9KOhms.

Otherwise, I don't have any other notes at the moment, I will let you know if I find anything else while I wait for a response on the crystal/oscillator.

Thanks,

Ryan

1.Customer are using crystal,

2.if using self-powered mode, can USB_VBUS  be routed to  3.3V rai  and R10 is 56.2KOhms?

Thanks.

Hi Jon,

Jon WANG said:

2.if using self-powered mode, can USB_VBUS  be routed to  3.3V rai  and R10 is 56.2KOhms?

USB_VBUS needs to connect to VBUS in order to detect when a USB device is connected. I would also recommend the 90.0KOhm resistor, as it is recommended in the design, but as long as the voltage on the pin doesn't exceed 1.155V, it should be alright:

You may be able to adjust the firmware to change this, but I can't say for sure whether this is possible or not, this would require investigation on the customers side.

Jon WANG said:

1.Customer are using crystal,

In this case, please ensure VSSOSC is not connected to PCB ground. The XI and XO pins can connect to the VSSOSC pin like how it is shown in the datasheet:

We also recommend a 1MOhm resistor connecting XI and XO, not a 2MOhm resistor:

Does this crystal need to be powered? I don't see any VCC on the schematic for the crystal.

Thanks,

Ryan