TUSB211 MFI Certification

Dear Diego..
I sent email to you...
Really thanks...

Hello Avraka,

I've reviewed the schematic and it is extrange that you only see the pulses on pin 1 and not on pin 8. Please verify that these pins are actually shorted.

Regards,
Diego.

Dear Diego...

I've attached the PCB drawing.

As you can see below, PIn #1 and #8 are shorted each other.

Could you explain what I have to to do to certifiy MFI?

Hi Diego

There is a additional test result of TUSB211, it is associated with the post of avraka.

1. Waveform on Pin 1(DM) when iPhone isn't connected to MFI tool

2. Waveform on Pin 1(DM) when TUSB211 is removed on PCB

How do you think about the waveform of No.1 and No.2?

Please let me know your recommended debug points and the solutions for passing MFI certification.

Thanks.

Hello Jeffrey,

    Based on No.2, seems that the issue is caused by the chip before the TUSB211 or layout, because this spikes must be seen on the pin 8 since they are shorten.

Regards,

Diego.

Hi Diego

I miswrote the description of No.2 in previous my post.

The correct description of No.2 is as follows.

2. Waveform on Pin 1 when TUSB211 is mounted on PCB and Pin 8 is opened.

(Pin 8 of TUSB211 isn't connected to DMOUT of CPU)

As you see, the spikes are seen on Pin 1 (Pin 1 and Pin 8 are shorten) although Pin 8 of TUSB211 isn't connected to DMOUT of CPU.

I don't think that the spikes is caused by the chip before TUSB211 because Pin 8 is opened.

How do you think about that?

Please let me know what is the cause of the spikes.

Thanks.

Regards

Jeffrey

Hello Jeffrey,

Please take a scope capture when the TUSB211 is not populated. The case when pin 8 is not connected is out of the spec, the pins 1 & 8 must be shorten always. if the issue is gone when there is no TUSB211, please use a different unit of the TUSB211.

Regards,
Diego.

Dear...

My customer also meet same situation.

customer use TPS2543+TUSB211.

test => MFI certification ATS test.

when connect ATS to the device, ATS side can not connect USB data.

if customer remove TUSB211 only, host can detect ATS side equipment.

Do you have any idea for closing this behavior?

Regards,