Be assigned to zener diode clamping the signal voltage of D+

General discussions about V-USB, our firmware-only implementation of a low speed USB device on Atmel's AVR microcontrollers
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apollononnno
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Be assigned to zener diode clamping the signal voltage of D+

Post by apollononnno » Tue Sep 02, 2008 1:26 pm

I connected an orange LED anode of 1.7v to D+ in substitution for zener diode and connected a green LED anode of 1.8v to D- and I connected both cathodes to another orange LED anode and connected the cathode to GND.
It could communicate definitely and produced little sparkle each time.

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christian
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Post by christian » Wed Sep 17, 2008 5:00 pm

Please note that not all orange and green LEDs have the same forward voltage. You must specify exact part types for the LEDs.

apollononnno
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I tried it about some LED.

Post by apollononnno » Thu Sep 18, 2008 6:14 am

I tried it about some LED.
When I used an electric current of 1mA, they occurred with the voltage of 1.8v from 1.5.v
(This applies to only me and may not apply to your device)
It was with generosity, and the sensitivity of the USB signal comparatively forgave these.
(Because I carried this out for an experiment purpose with an amateur, I cannot use it for close commercial eyes)
Everybody may not obtain the parts which I tried.

The LED of the board of the image does not understand a name.
I used next with another board.
STANLEY
BG1101W_1mA_1.8V_GaP
AA1101W_1mA_1.8V_GaAsP
They glitter at an H level and are easy to make the diagnosis of the circuit.
Image

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