HD3SS3220: V(DFP_CC_HIGH) is 1.6V ,not 2.6V

can you read what current state wth I2C?

Regards

Brian

HI,BRIAN.

no use i2c, only ADDR is pulled up.

Is i2c mode  prior to GPIO mode? i need confirm.

no, I mean if you can use I2C, then you can read current state in I2C and also measure  voltgae on CC pin to see if matched in data sheet.

Best

Brian

ok, i'll try

Pls keep us update.

hi,dear.

According to USBC spec Table 4-10 in Page149, 3A at 5V, Rp is 10K ,Rd is 5.1K. The voltage of CC is about 1.69V, not said 2.6V in the datasheet.

In addition, in HD3SS3220 datasheet Page6, what is meaning of V(UFP_CC_HIGH) and V(DFP_CC_HIGH)? I think they are the same voltage while UFP connected to DFP, the voltage between the Rp and Rd?

thank you

Rp should be 56k?

Best

brian

hi, dear.

Sorry to change the content. Now there are more important questions as above.

Rp should be 56k?-------Is it the answer about my above question? 

in TI CC controller Rp is always around 56k.

Best

Brian

If CURRENT_MODE is set to 3A, according to USBC SPEC Rp is 10K ,Rd is 5.1K. The voltage of CC is about 1.69V, where is V(UFP_CC_HIGH) =2.6V come from?

In addition, in HD3SS3220 datasheet Page6, what is meaning of V(UFP_CC_HIGH) and V(DFP_CC_HIGH)? I think they are the same voltage after UFP connected to DFP, the voltage of CC line between the Rp and Rd?

Hi, Dear.

1. UFP_CC_HIGH is for sink  circuit and DFP_CC_HIGH is for source circuit, it  should be different.-------I think they are only different name. one is for DFP, another is for UFP, that's all. But the voltage that the name acted is the same. As DFP according to datasheet,  V(DFP_CC_HIGH) mean the CC line voltage level for detecting a UFP attach when DFP and advertising 3-A.Obvisously CC line voltage level is based on the Rp (10K at 3A) and Rd（5.1K constantly), which Rp is pullup to 5V and Rd is pulldown to 0V and two sides CC line is short together. The same is to V(UFP_CC_HIGH). Is my understanding right?

So DFP CC line voltage level is only about 1.69V, where is V(DFP_CC_HIGH) cover between 2.46V to 2.74V come from? 

2. Rp will be different in DFP based on different current setting.----------- I know. There are three value of resistance,56K,22K and 10K. So i highlight CURRENT_MODE is set to 3A，at this moment Rp is 10K.

Thank you

for DFP

for UFP

Pls see USBC spec.

hi, dear. I feel that you answer beyond my question. 

Here i quote it again. Obvisously CC line voltage level is based on the Rp (10K at 3A) and Rd（5.1K constantly), which Rp is pullup to 5V and Rd is pulldown to 0V and two sides CC line is short together.  V(DFP_CC_HIGH) should be equal to V(UFP_CC_HIGH). Is my understanding right?

So DFP CC line voltage level is only about 1.69V, where does the value of V(DFP_CC_HIGH)  that cover between 2.46V to 2.74V come from? 

Source detect and sink detect voltage should be different, but I will find out.

regadrs

brian

hi, dear. I look forward to your reply.

But at present, I had a serious problem. HD3SS3220 works in GPIO Mode (ADDR pin NC) and DFP mode (PORT is High). When the cable plug into the type-c receptacle, one of the CC line voltage is normal (ie about 1.7v) and another CC line voltage is abnormal (ie. about 0V). I measure them from the DFP side (host).  Theoretically as the DFP, the 0v voltage of one of CC line is impossible. Changing the cable orientation or flipping the cable is the same result. I checked the ID (used for VBUS switch) and DIR signals, their behavior are all right, obviously the HD3SS3220 work well.

So is it possible? Please give me some advise.

Thank you

hi,dear:

To add a few content. My board (using HD3SS3220) acts as DFP. When no tablet connected, my board two cc lines voltage are 5V. Once tablet is connected, one of  CC voltage is 0V(abnormal), and another CC line voltage is 1.7V (normal). The first picture is no tablet.The second picture is having tablet.

When tablet is connected, ID (used for VBUS switch) is low and DIR signals is 1 or 0 , their behavior are all right.

So is it possible? Please give me some advise. 

Thank you

this looks normal, so what is your question?

Regards

Brian

Hi dear.

My question is why one of  CC voltage is 0V, normally it should be 5V because i measure it from DFP side (HD3SS3220 acted as DFP).

Thanks

hi, dear.

Thank you for your reply. From your picture, I think it is only a picture, no theoretical foundation.

My theoretical foundation is USB SPEC or the picture as below. Although CC2 is not used, it is pulled up to 5V together with CC1 in DFP side.

So none of CC voltage should be 0V, normally it should be 5V always even if there is a cable.

Is my understanding right?

Thank you again.

this is typical type-C cable.

Do you mean my cable contains Ra?

do you use typical plug-plug type-Cc cable?

Best

Brian

Hi,dear.

Yes, it is exactly a plug-plug type-C cable.