TUSB8041: What is the monitor threshold of TUSB8041 USB_VBUS pin

Wayne Wang20

Part Number: TUSB8041

Hi team,

My customer is developing TUSB8041. In our datasheet, there is a description about the USB_VBUS pin as below picture.

With a 90.9k and 10k resistor divider, the USB_VBUS pin voltage=5V*10/100.9=0.496V. But customer doesn't have a proper value resistor in their hand. So they want to change 90.9kohm resistor to another resistance value. But our datasheet doesn't explain what is the monitor threshold of USB_VBUS pin. So can you help provide this information so we can calculate a proper value resistor divider to satisfy USB_VBUS pin monitor threshold. Thanks.

Best regards,

Wayne

over 4 years ago

0 JMMN over 4 years ago

TI__Guru 60870 points

Hi Wayne,

When VBUS is on, the voltage at the pin should be at least 450 mV. I would recommend setting the expected ON point a bit higher than 496 mV if they are not using 1% resistors to add margin.

Regards,

JMMN

0 Malik Barton57 over 4 years ago

TI__Guru 64326 points

HI Wayne,

The resistor diver should be sized to keep USB_Vbus around ~500 mV when VBUS is asserted. Vih(min) = 400 mV, Vih(max)=1.155V.

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TUSB8041: What is the monitor threshold of TUSB8041 USB_VBUS pin