How to connect VBUS line for LPCExpresso 1769

[lpcware]

Content originally posted in LPCWare by mayur.p.85 on Wed Mar 12 14:11:43 MST 2014
HI all

can anyone tell me or tried connecting VBUS line and generate VBUS interrupt for detecting
USB connection for LPCExrpesso board?

I am interested to know how to connect VBUS line, I checked the schematic but see
that p1.30 line is mapped for ADC already. Using pinselect register functionality I guess
I can change the PIN functionality but any necessary Hardware/resistor I need to put for it?
Does it generate an interrupt or any configuration required to generate interrupt for VBUS?


Please let me know.

[lpcware]

Content originally posted in LPCWare by Tsuneo on Fri Mar 28 12:05:58 MST 2014
Answered in this post,
http://www.lpcware.com/content/forum/lpc1343-vcom-driver-windows-7-64bits#comment-1136293

Tsuneo

[lpcware]

Content originally posted in LPCWare by liaochengyi on Tue Mar 25 00:28:35 MST 2014
Dear Tsuneo,

I have a question about the host app is coded in VB and always do IOCTL_SERIAL_WAIT_ON_MASK, and loss some task need to do.

I am used the lpc11u37 example code.

May I ask, how to solve this issue?

http://www.lpcware.com/content/forum/how-handle-bulk-zlp-lpc11u37-usbdromcdc-example-code

Thank you for your help.
Best regards,
Chengyi

[lpcware]

Content originally posted in LPCWare by Tsuneo on Mon Mar 17 18:01:34 MST 2014
On bus-powered device, VBUS pin of LPC family is not needed to be connected to VBUS (5V) pin of the USB connector. When VBUS function is not mapped to any pin, internal VBUS input is connected to VDD.

For self-powered device, like your case,
1) input protection resistor
VBUS pin of the MCU is connected to connector VBUS (5V) across a protection resistor, as suggested by serge. The value of this resistor is around 100 - 4k7 ohm.

2) on-chip port pull-down
pull-down is enabled at the VBUS pin by PINMODE3 register.

3) capacitor at connector VBUS (5V) pin
According to the USB spec, a capacitor is required across connector VBUS (5V) pin and GND. The spec specifies the value in this range, 1 - 10 uF, for ADP (Attach Detection Protocol).
(Device Capacitance ECN.pdf)

Tsuneo

[lpcware]

Content originally posted in LPCWare by serge on Mon Mar 17 08:05:34 MST 2014
Maybe you can use the circuit on page 5 of this board as an example: LPCXpressoLPC1347revA

[lpcware]

Content originally posted in LPCWare by mayur.p.85 on Sat Mar 15 04:52:43 MST 2014
actually I forgot to mention the controller I am talking about. It is LPC1769.
@Martin: Can you point me to any reference? I also checked User Manual from LPC website for LPC1769 which does shows the connection of
VBUS line in case of Device configuration directly without any circuits. It would be really helpful if you can let me know any reference.

[lpcware]

Content originally posted in LPCWare by Martin84 on Thu Mar 13 01:48:26 MST 2014
Some LPC controller need an additional circuit in front of the vbus input pin, because this pin isn't 5V compatible, when the 3.3V Supply is absent.