Worst-case voltage Drop - HX2LV

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ShMi_1495391
Level 4
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Hello

I have a question about CY7C65632-48AXC.
There is description below in the "Operating Conditions (page 19)" of HX2LV datasheet.
https://www.cypress.com/file/114101/download
「5 V supply voltage to ground potential ......4.75 V to +5.25 V」

While, there is description below in the "7.2.2 Voltage Drop Budget(page 175)" of the USB 2.0 specification.
「The voltage supplied by low-powered hub ports is 4.4 V to 5.25 V.」

If the voltage drop is the worst, can HX2LV not keep with this USB 2.0 specification?

Best Regards

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1 Solution

Hi,

Thank you for your clarification.

We are so sorry, our HX2VL the operating range on datasheet is not up-to-date.

VBUS range will be updated and the value will be 4.5V (min) - 5.0V (typ) - 5.5V (max). (Though datasheet update date is not clear, so far.)

Hence, HX2VL can handle the Worst-case Voltage Drop (4.625V supply).

Best regards,

Hirotaka Takayama

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HirotakaT_91
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As per the 001-67568 Rev. *L datasheet, the input voltage to the built-in regulator is within the 4.75 V to 5.25 V range.

The 3.3 V power output is guaranteed by an internal voltage reference circuit by following above description.

Best regards,

Hirotaka Takayama

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Hi,Takayama-san

When Host outputs 4.75V, the voltage may drop to 4.625V at worst.

pastedImage_0.png

In other words, does it mean that HX2LV needs to make the portion of the red circle be "4.75 V" in anticipation of voltage drop?

Or does it mean that there is no problem because the design is in anticipation of this voltage drop?

Best Regards

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Hi,

Thank you for your clarification.

We are so sorry, our HX2VL the operating range on datasheet is not up-to-date.

VBUS range will be updated and the value will be 4.5V (min) - 5.0V (typ) - 5.5V (max). (Though datasheet update date is not clear, so far.)

Hence, HX2VL can handle the Worst-case Voltage Drop (4.625V supply).

Best regards,

Hirotaka Takayama

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Hi,Takayama-san,

Thank you for your answer.

By the way, is it possible to tell me when update date is decided?

Best Regards

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Hi,

I am sorry we are not able to say when will be updated.. (Not decided the schedule for it.)

We will do our best.

Best regards,

Hirotaka Takayama

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