Using USB device - is VBUS needed?

[lpcware]

Content originally posted in LPCWare by sjalloq on Sun Nov 13 11:51:47 MST 2011
Hi there,

I'm going to be using the USB device port on the LPC17xx LPCXpresso board.  What is the minimum I need to add to my PCB in order to support this?

Looking at the LPC17xx User Manual it seems that VBUS is pulled up internally by default so I'm assuming I can get away without adding the external pullup?

Secondly, the series terminating resistors and D+ pullup are already populated on the board.  Am I set to go by just connecting D+ and D-.

Finally, if I want to run bus powered, what do I need to take into consideration for hooking up the 10-pin SWD connector?

Thanks.

[lpcware]

Content originally posted in LPCWare by Ex-Zero on Sun Nov 13 15:42:53 MST 2011

---

Quote:

What is the minimum I need to add to my PCB in order to support this?

---

[ATTACH]592[/ATTACH]

USB connector (D+, D- and GND)

---

Quote:

I'm assuming I can get away without adding the external pullup?

---

Yes

---

Quote:

Secondly, the series terminating resistors and D+ pullup are already populated on the board. Am I set to go by just connecting D+ and D-.

---

Yes, resistors and USB-connect circuit are on the board.

---

Quote:

Finally, if I want to run bus powered, what do I need to take into consideration for hooking up the 10-pin SWD connector?

---

Connect VCC of your USB connector to VIN (J6-2) and you are bus powered :eek: