![]() |
Maximum current draw through DIO port
What is the maximum current draw through a DIO port. Our team is planning on adding some LED's for visible signal indicators, and the LED's I have found draw 80ma. Is that too much to drive using 5 volts directly from the roborio DIO port, or would it be better to operate these off of 12 volts via a spike?
|
Re: Maximum current draw through DIO port
The 5v rail allows a max of 1a (combined so all other 5v pins are included).
https://decibel.ni.com/content/servl...20Overview.pdf |
Re: Maximum current draw through DIO port
Over the years. The few custom circuits I have inspected. Generally come to the input, output side. Not sure what max amp draw is or total draw is. Sounds like you are low enough. Thank You Mentor Mac
|
Re: Maximum current draw through DIO port
Page 4 of the RoboRio spec says the DIO lines can sink or source 4 mA. Unless I am missing something, happens often :), no, you cannot feed the LED directly off a DIO line.
Output high is 3.3 volts nominal. |
Re: Maximum current draw through DIO port
I'd recommend using a Spike for LEDs or a custom circuit that only uses the DIO signal as a control.
|
Re: Maximum current draw through DIO port
AndyMark has a DC/DC converter that will output 5V DC 10A max $18
http://www.andymark.com/product-p/am-3068.htm |
Re: Maximum current draw through DIO port
It's hard to believe that a spike draws that much less than a single LED, but there is enough doubt in my mind that I think it's best to just use a spike. I can size my resistor for 12 volts instead of 5 (or 3.3).
|
Re: Maximum current draw through DIO port
Spike Specifications
Quote:
|
Re: Maximum current draw through DIO port
Quote:
BTW: I think the spike can switch 5v, so you don't have to switch 12v and step it down as much. |
Re: Maximum current draw through DIO port
The spike has been tested for the relay ports. I don't know if they have been tested for a DIO pin. The specs are different. The NI guys say the RoboRIO IO have been tested by teenagers & is nearly indestructible. But I am superstitious (or maybe I have more efficient teenagers. :] )
The input voltage for the spike's relay section is 12V nominal. I do not know if it will work at 5v. |
Re: Maximum current draw through DIO port
You also have a 5V 2A off from your VRM this year - two of them! one is for your radio, the other one we've hooked up to an LED strip.
|
Re: Maximum current draw through DIO port
Quote:
Quote:
|
Re: Maximum current draw through DIO port
Quote:
AndyMark has a DC/DC converter that will output 5V DC 10A max $18 http://www.andymark.com/product-p/am-3068.htm |
Re: Maximum current draw through DIO port
J,
When you speak of LEDs, many of us naturally think an LED string. A single LED can be switched by the DIO through a switching transistor or other driver. If your LED can operate (actually produce light) at 4 ma, you can sink that much current as quoted by Frank above. |
Re: Maximum current draw through DIO port
Quote:
|
| All times are GMT -5. The time now is 20:35. |
Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi