TUSB216I:

Hello,

Can you share the compliance report, so I can see how it is failing and what test is running?

Thanks,

Nicholaus

Hi Nicholaus,

Attached herewith the test reports. All the tests are done as follow.

1. HS Device
2. Far End
3. 2m Pre-channel cable and 2m Post-channel cable

Test 1 was performed with RX_SEN=mid and BOOST=1.

Test 2 was performed with RX_SEN=mid and BOOST=3.

Test 3 was performed with RX_SEN=high and BOOST=3.

All the 3 tests failed the far-end compliance test.

Appreciate your help. Thanks.

Test1_device test_high speed _far end_RX_SENmid_BOOST1_2mPreChannel_2mPostChannel.pdfTest2_device test_high speed _far end_RX_SENmid_BOOST3_2mPreChannel_2mPostChannel.pdfTest3_device test_high speed _far end_RX_SENhigh_BOOST3_2mPreChannel_2mPostChannel.pdf

Best regards.

Oo

Hi Oo,

The voltage output differential (VOD) for all of these tests is quite low.  Does this compliance result change when you use a different host?

My recommendation for this host is to try increasing the DC_GAIN on the TUSB216I to as high as possible and retest. 

Regards,

Nicholaus

Hi Nicholaus,

The BOOST level of the TUSB216I was set to level 3 for both Test 2 and Test 3. But, I am unable to see any obvious improvement in the VOD. Meanwhile, I am arranging to test with different device. Appreciates your help. Thanks.

Best regards.

Oo

Hi Oo,

I see.  Are you able to use I2C mode?  In I2C mode you are able to adjust the DC_Boost level higher than using pin-strap settings.  The field DCB_LVL in the DC_BOOST register (Section 7.5.3, 0x0E) can be adjusted to 0x0F, which is the highest DC_Boost setting.  Don't forget to change the Configuration register from 0x00, change the DC setting, and then back to 0x01.

The DC boost feature on the TUSB216I will only change the VOD slightly, but this should give the greatest improvement.  The VOD is suspiciously low in the compliance tests results, it should be almost double where it is at.  This is what makes me think that maybe the signal source is weak and checking with another device would be helpful.

Regards,

Nicholaus

Hi Nicholaus,

I found two series resistors, each at the D+/D- of the host. Hence, I replaced them with 0 ohms. The results are attached herewith.  The results confused me about the settings. Why BOOST=1 & RX_SEN=mid has a better VOD than BOOST=3 & RX_SEN=high for the 2m Pre-channelUSB2d0 Cable Performance Review.pdf and 1m Post-channel? Now, I am trying with a 6m pre-channel and 1m post-channel. Will update you the result. Appreciate your help. Thanks.

Best regards.

Oo

Hi Oo,

Are there any follow-up questions? 

Regards,

Nicholaus