topic Re: Schema for USB host port configuration in LPCXpresso IDE

Schema for USB host port configuration

lpcware — Wed, 15 Jun 2016 23:43:42 GMT

Content originally posted in LPCWare by DavidLola on Mon Apr 28 02:00:14 MST 2014
Hello
In the datasheet of NXP1769, there is a schema for USB host port configuration, but i don't understand is why there is no 5 V for the USB-A connector. The USB_PWRD which is connected with Vbus is not 5V. So what is the real schema for USB host port configuration?

Thank you

Re: Schema for USB host port configuration

lpcware — Wed, 15 Jun 2016 23:43:43 GMT

Content originally posted in LPCWare by DavidLola on Mon Apr 28 02:02:36 MST 2014
And at the same time, if i don't have the LM3526-L, is the schema still running or not?
Thank you

Re: Schema for USB host port configuration

lpcware — Wed, 15 Jun 2016 23:43:44 GMT

Content originally posted in LPCWare by Pacman on Mon Apr 28 08:09:42 MST 2014
Assuming you're referring to Figure 31, "USB host port configuration".
As I understand the schematics, is that VBUS is connected to LM3526's OUTA.
The LM3526 would be connected to +5V and the microcontroller's USB_PPWR and USB_OVRCR.
USB_PPWR is "port power enable", USB_OVRCR is "over-current status". USB_PWRD is "port power status".
Perhaps you didn't notice the difference between PPWR and PWRD ? :)

Anyway, I believe it would probably work (temporarily) if you connect it to +5V via a 500mA fuse, until you get your USB-power-switch, which is what LM3526-L is.
There are many alternatives to LM3526-L; I'm personally considering Micrel's MIC2005A-2YM6.
I have not verified if it will work, though, but the price isn't too high.

Re: Schema for USB host port configuration

lpcware — Wed, 15 Jun 2016 23:43:44 GMT

Content originally posted in LPCWare by DavidLola on Mon Apr 28 08:26:28 MST 2014
Thank you first for your answer.

Normally, the Vbus of the USB-A connector should be connected to a 5V tension(in a host mode), is that right?
So i didn't connect the Vbus to the LM3526's OUTA and USB_PWRD, but to a 5V tension.
And i use the example of LPCopen mass storage host, the board is LPC1769 REV B.

But it doesn't work.

Can you tell me what's the problem?

Re: Schema for USB host port configuration

lpcware — Wed, 15 Jun 2016 23:43:45 GMT

Content originally posted in LPCWare by Pacman on Mon Apr 28 10:10:19 MST 2014
Hmm, I don't want you to fry your LPC, so I'll ask if you could post a schematic of your current USB-connection to the LPC ?