TPS2511 failing BC1.2 automated testing

Hi Todd,

Can you please advise if all the TSP2511 units tested failed or just some devices?

Thanks, Carlo.

Carlo,

All the 5pc we have tested fail.  Its easy enough to see the slow change times on a CRO.

Best Regards, Todd/Daniel

Daniel,

BC1.2 test is targeting to tesBC1.2 shorted mode, which D+/D- is shorted together, floating with a resistor.

TPS2511 supports BC1.2 devices charging, but it's not fixed at BC1.2 shorted mode:

TPS2511 supports Apple divider mode, BC1.2 mode, and Galaxy Tab 1.2V/1.2V divider mode, so it's a mix of different charging IDs and automoticly switch over based on what types of devices pluged-in.

TPS2511 default 2.7V/2.0V Apple Divider mode, and after BC1.2 devices pluged in, it can regonize and switch over to BC1.2 shorted mode after that.

BC1.2 compliance plan only targeting to test BC1.2 shorted mode only, it's not suitable for test for smart chargers like TPS2511.

Vincent,

We are aware of the features. The BC1.2 Test covers all of the features that you have mentioned, The TPS2511 passed the other elements of the BC1.2 (Required voltages), we're targeting the area that it had failed, timing. The TPS2511 IC is 130ms too slow for each of the modes and has triggered a failure for the compliance test.

Regards,
Daniel/Todd.

Daniel,

I see. The reason why we use 130ms longer time is because we need to filter the noise which cause TPS2511 mistrigger into wrong mode. Especially iPad first plug in, if use short timer, the noise of first plug in iPad will trigger TPS2511 from correct Apple divider mode into wrong mode.

It's based on our experience and test data, we choose the best timer to be able to support as many devices as possible, but unfornately, it's longer than BC1.2 test expected. As I mentioned in last post, TPS2511 is more than BC1.2, not designed dedicated for it, instead to cover all major stream devices.

We are experiencing precisely the same failure in the DCP Handshaking Test.  Is there anything that can be done to make the TPS2511 pass the automated BC1.2 test?

Hi Jory,

We will dig through the archives to see if any new information is available. TPS2511 has not undergone any design changes but it is possible the BC1.2 test equipment has. We'll report any new information when/if it becomes available.

Hi Jory,

What did customer do when they test the DCP handshaking test ?  Could you please kindly have a detailed explanation? Thank you !

Our unit failed an automated test performed by Allion Engineering Services.  Allion tested our unit to the Battery Charging Specification Revision 1.2.  It failed precisely in the same fashion as Daniel Vincent (the original poster) described.  There doesn't appear to be a way to post the test report or I would do so.

Our unit passed all of the tests except for Section 8.3 DCP Handshaking Test and Section 8.4 DCP Resistances and Capacitance Tests.

Here's the description of the first failure:

Here's the second failure:

According to Vincent Wang's post earlier in this thread, these two failures are due to the fact that the TPS2511 does not meet the BC1.2 requirement for the speed of detecting mode changes.

I would like to know which of TI's DCP charge controller IC's will pass the automated BC1.2 compliance test. 

Apparently the e2e Forum will not permit the posting of images into the text.  That's REALLY not helpful.  I'm trying again:

One more time:

Our unit failed an automated test performed by Allion Engineering Services.  Allion tested our unit to the Battery Charging Specification Revision 1.2.  It failed precisely in the same fashion as Daniel Vincent (the original poster) described.  There doesn't appear to be a way to post the test report or I would do so.

Our unit passed all of the tests except for Section 8.3 DCP Handshaking Test and Section 8.4 DCP Resistances and Capacitance Tests.

Here's the description of the first failure:

Here's the second failure:

According to Vincent Wang's post earlier in this thread, these two failures are due to the fact that the TPS2511 does not meet the BC1.2 requirement for the speed of detecting mode changes.

I would like to know which of TI's DCP charge controller IC's will pass the automated BC1.2 compliance test.  

Hi John,

Thanks for the response!

Your response seems to imply that the compatibility problem with the TPS2511 is due to the fact that the TPS2511 doesn't implement "VBUS discharge".  I can kind of guess what that means, but it would be good to understand what that means.  The earlier posting from Vincent Wang said the problem was with a longer than specified DCP Handshaking time that was done to make the TPS2511 less prone to noise.  These two explanations (VBUS discharge and DCP Handshaking time) appear to be completely different.  Are they different or just different words for the same thing?

We're trying to get a feel for what issues we're likely to encounter in the field if we continue to use the TPS2511 instead of redesigning with a different part.  To that end, I would like to get a list of devices that have been shown to work with the TPS2511.  Where would I find that?

What device(s) does TI recommend for new designs if the goal is to be compatible with the most devices? 

HI Jory,

I believe you are correct in that these are different aspects of the same thing. The BC1.2 compliance checklist has DCP16 , CDP14, and SDP3 - Does the unit provide VBUS discharge functionality? During Renegotiation there are parts of the spec that ask for VBUS to be discharged to <0.7V. Devices like the TPS2513 and TPS2514 can not do that as they do not have control of VBUS.

As for compliance, we actually work with pretty much everything we test. To be clear, I am not sure which products shipping today we would not work with. So all of these are compatible. However, if you want to support universal charging and get USB-IF logo certification then the TPS2549 is probably the best choice. This comes up a lot for customers looking to support Car-play.

Regards