LPC MicrocontrollersのトピックLPC55S6X USB0 in host mode

LPC55S6X USB0 in host mode

manuela_mendez — Sun, 23 Feb 2025 14:50:13 GMT

Hello NXP Experts,

I've few clarification questions on using USB0 as host on LPC55S6x:

UM11126, rev2.7, p832 table 780 says: "Enable USB0_VBUS pin for correct host operation. For example, it is required detect a change in the connection status."
1. what is the correct way to achieve this? can VBUS0_VBUS be tied permanently to 3.3v?
2. what is the pullup recommendation to minimize the current draw? is there anything else required at the schematic level?
Could you explain USB0_VBUS role in host mode? LPC55x documentation has no coverage on this. Is there an older MCU doc that talks about this?
Does LPC55S6X-EVK support using USB0 as host? I see this being exposed as PIO22 on the headers, but not sure what else is needs to be done to get the host functional
Is there a SDK example that uses USB0 has host?

Thanks in advance!

Re: LPC55S6X USB0 in host mode

Alice_Yang — Mon, 24 Feb 2025 10:17:56 GMT

Hello @manuela_mendez

The USB0_VBUS should be connected to 5V.
When USB0 functions as a host, the USB0_VBUS is used to supply power to the USB device and also to detect whether the device is connected or disconnected.
The LPC55s6x-EVK supports USB0 as a host. Please refer to the LPCXpresso55s69 User Manual for configuring the hardware. Hardware please refer to schematic of lpcxpresso55s69-evk.

https://www.nxp.com/webapp/sps/download/preDownload.jsp?render=true

https://www.nxp.com/webapp/Download?colCode=LPC55S69-SCH

The USB host example uses USB0 by default. Please refer to the relevant documentation for further details.

Alice

Re: LPC55S6X USB0 in host mode

manuela_mendez — Mon, 24 Feb 2025 11:58:14 GMT

Hello @Alice_Yang

Thanks for the quick response. I'll look into the resources you have provided.

Regd. you comment "The USB0_VBUS should be connected to 5V" --

on p44, Rev. 2.3 of LPC55S2X_LPC552X datasheet it states the following:

[6]
The corresponding VBUS must be connected to supply voltage when using the USB peripheral. USB0_VBUS is not 5 V tolerant pin and is tolerant up to
3.6 V only when the VDD is at operating level (minimum: 1.8 V). USB1_VBUS is 5 V tolerant pin regardless if the VDD supply is present or not.

it doesn't talk about the host mode, but still it is confusing - that was the reason for me to think it needs to be connected to 3v3.

Re: LPC55S6X USB0 in host mode

Alice_Yang — Wed, 26 Feb 2025 06:55:25 GMT

Hello @manuela_mendez

Yes, you are right. So design USB0_VBUS as below:

Alice

Re: LPC55S6X USB0 in host mode

manuela_mendez — Wed, 26 Feb 2025 20:23:45 GMT

Hello @Alice_Yang: thank you for the confirmation!