Outputs on Duet 2
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Hi,
I need to use an output with 3.3V to 5V - 25mA on my Duet 2 card and found that I can only use and control the expansion pins on the same card. I believe that the amp is fine but still wondering about the maximum amp that this pins can handle? I am planning to use the heater outputs shown below.
Is this all right? can I control these outputs as I need?Thanks
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What exactly are you trying to drive from those pins? They should be considered signal pins only and cannot power a heater directly.
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@Phaedrux I need to turn on some sort of laser diode which needs an output with 3.3V to 5V and 25mA. Can't I just use them as output signals and turn them on or off when wanted? Also, to control some lights as well?
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I need to use an output with 3.3V to 5V - 25mA on my Duet 2 card …
I believe that the amp is fine but still wondering about the maximum amp that this pins can handle?Most of the signals on the expansion bus originate from the Atmel MCU, so they are unbuffered and have a rather limited fanout. You can look-up the specs from the data sheet of the MCU, but don’t expect them to deliver more than 10 mA at 3.3V each. I suggest to use some buffers or inverters from the 4000 or 7400 series.
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@infiniteloop Thanks for clarifying. I guess that I misunderstood the documentation about these pinouts.
I just need one output for max 25mA, and can only see the PS-ON/GND as a possible usable output for my laser diode?! and I need the PWM outputs for fans. if you have any recommendation will be highly appreciated. Thanks!
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@Muhammed said in Outputs on Duet 2:
@infiniteloop Thanks for clarifying. I guess that I misunderstood the documentation about these pinouts.
I just need one output for max 25mA, and can only see the PS-ON/GND as a possible usable output for my laser diode?! and I need the PWM outputs for fans. if you have any recommendation will be highly appreciated. Thanks!
I can manage to have a spare output from the PWM FANS outputs, then I think it should be fine to use it, but I need to be careful about setting the voltage to the correct value. Will this be ok?
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the PS-ON/GND as a possible usable output for my laser diode
From the lion's mouth: "The PS_ON output is a PMV40UN2 mosfet (good for up to 30V and 3A) on the Duet WiFi". So that's an N-MOSfet (switching to GND) - should be powerful enough to control (not: to power) your laser.
I can manage to have a spare output from the PWM FANS outputs, then I think it should be fine to use it, but I need to be careful about setting the voltage to the correct value. Will this be ok?
Sure, these use N-MOSfets as well, so switch whatever voltage you supply on the other side to GND. Maybe you need to provide a pull-up resistor, depending on the signal required.
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@infiniteloop Thank you so much for your reply. This will give me a push forward.
