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Dear, Sir.

I am having a  question about TUSB320 VBUS_DET.

6 page on the datasheet, external 900kOHM and typ. 3.3V thereshold

is defined. Also intrernal 95kOHM pull-down resistance is defined.

I suppose VBUS on USB TYPE-C will be 5V/500mA, 1.5A, 3A.

If the bias on VBUS_DET was the divided by resistors;

5V * 95kOHM/995kOHM = 0.48V

If true,  VBUS_DET voltage never across the threshold voltage.

Does it mean VBUS_DET was invalid unnder VBUS 5V condition?

Best Regards,

H. Sakai

• Hello hideyuki,

I am reviewing the spec with my team and I will provide a feedback ASAP.

Regards,
Diego.
• In reply to Diego Cortes:

Dear, Diego-san.

Sorry again.

This matter is getting important with my customer.

Best Regards,

H. Sakai

• In reply to hideyuki sakai:

Hello Hideyuki-san,

I am sorry for the delay, the datasheet is under update process. We are including a note where we established that the threshold voltage is for direct VBUS, therefore the minimum detected value on the VBUS pin would be 2.95V * 95kOHM/995kOHM =0.28V

Regards,
Diego.
• In reply to Diego Cortes:

Dear, Diego-san.

Thank you so much for your valuable information.

And sorry to disturb your job, again and again.

Best Regards,

H. Sakai

• In reply to hideyuki sakai:

Dear, Diego-san.

My customer is making several questions about TUSB320HAI.

1. Vbus Maximum Voltage.

VBUS_DET max voltage is defined as 4V.

Does it mean real Vbus Maximum voltage will be 42V although

recommended is max 28V?

2. CC1/CC2 voltage under DFP-DFP connection.

VDD=3.4 ~ 4.2V. VBUS = 5V. Rp(pull-up) is active inside of IC.

I wonder CC1/CC2 is no problem because VDD+0.3V is defined on

maximum ratings?

3. VBUS_DET external pull-up.

1Mohm is mounted on TUSB320-HA-EVM. It is making confusion on

customer side.

Please clarify real VBUS_DET threshold voltage.

4. Hysteresis on VBUS_THR.

Does VBUS_THR have hysteresis? If has, Please explain rising time &

falling time to avoid miss-understanding.

Best Regards,

H. Sakai

• In reply to hideyuki sakai:

Hello Sakai-san,

First of all let me tell you that the 6V maximum voltage on the CC pins is also valid for the TUSBHAI & TUSBLAI.

Now for VBUS_DET: 3.8V is the maximum VBUS_DET recommended value, which means that you can apply up to 4V to VBUS_DET without damage the pin, however we only warrant its proper functionality under the recommended operating conditions. This condition is also valid using the 1MOhm resistor between VBUS_DET & VBUS. I don't have the hysteresis value for the VBUS threshold, however the chip implements a debounce timer with a default value of 168ms (please see the register map, address 0x0A bits 7:6).

CC pins: There is no issue since the actual maximum rating for the CC pins is 6V. (the datasheet is being updated).

Regards,

Diego.

• In reply to Diego Cortes:

Dear, Diego-san.

Thank you for your valuable information.

1. VBUS recommended voltage is 4 ~ 28V.
I think it might be 4 ~ 6V considering all situation such as CC1/2 voltage under Rp-Rp connection.
How do you think about it?

2. RVBUS recommended value is 891kOHM ~ 909kOHM, 1MOHM is out of that.
Do you have a plan to revise the datasheet?

Best Regards,
H. Sakai

• In reply to hideyuki sakai:

Sakai-san,

This is my feedback:

1) You are correct, the voltage on the VBUS_DET terminal will be lower than 6V.

2) It is under discussion.

Regards,

Diego.

• In reply to Diego Cortes:

Dear, Diego-san.

I am expecting to brush up the datasheet definition contents to avoid the customer's

misunderstanding & confusion, especially about BVUS recommended voltage & RBUS.

Best Regards,

H. Sakai

• In reply to hideyuki sakai:

Dear, Diego-san.

Thank you for your support and sorry to disturb your job, again.

Before, we discussed about following topics.

1. VBUS recommended voltage is 4 ~ 28V.
I think it might be 4 ~ 6V considering all situation such as CC1/2 voltage under Rp-Rp connection.
How do you think about it?

2. RVBUS recommended value is 891kOHM ~ 909kOHM, 1MOHM is out of that.
Do you have a plan to revise the datasheet?

I have checked the latest DS on website, but VBUS & RVBUS definitions are no changed.