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Juri74

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Joined: 06/02/2012
Location: Italy
Posts: 162

Posted: 05:02am 16 Jul 2013

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please a quick question:
i've to use digital outputs but with "ones" to 3.3v and not 5v, i mean when i use the command PIN(n)=1 and pin N change it state from zero to one it should have 3.3 volt, i do not remember which outputs to use... 11 to 20? or 1 to 10?

thank you
JuriEdited by Juri74 2013-07-17

MicroBlocks

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Joined: 12/05/2012
Location: Thailand
Posts: 2209

Posted: 05:30am 16 Jul 2013

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The outputs are always 3.3 volt.

5v is only important when you use it as an input. Then the pins have to be 5v tolerant otherwise you can damage the PIC32 chip.

relevant part from the manual:
[quote]
The original Maximite has 20 I/O pins numbered 1 to 20. Pins 1 to 10 can be used for analog input and digital
input/output with a maximum input voltage of 3.3V. Pins 11 to 20 are digital only but support input voltages
up to 5V and can be set to open collector.
The DuinoMite has completely different and confusing allocations. See "DuinoMite MMBasic ReadMe.pdf"
Normally digital output is 0V (low) to 3.3V (high) but you can use open collector to drive 5V circuit. This
means that the pin can be pulled down (when the output is low) but will go high impedance when the output is
high. So, with a pull up resistor to 5V an output configured as open collector you can drive 5V logic signals.
Typical value of the pull up resistor is 1K to 4.7K.
[/quote]

Microblocks. Build with logic.

Juri74

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Joined: 06/02/2012
Location: Italy
Posts: 162

Posted: 06:35am 16 Jul 2013

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thank you TZA, i missed that info!

djuqa

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Joined: 23/11/2011
Location: Australia
Posts: 447

Posted: 01:25pm 16 Jul 2013

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And despite what most here call them the outputs are OPEN DRAIN not open Collector so normal MOSFET handling/current limits apply.Edited by djuqa 2013-07-17

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JohnS
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Joined: 18/11/2011
Location: United Kingdom
Posts: 3804

Posted: 07:56pm 16 Jul 2013

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I have a rather poor understanding of what those "normal" limits are - please explain or can you provide a URL of somewhere with a summary?

John

dergi
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Joined: 06/08/2013
Location: Canada
Posts: 1

Posted: 06:35am 07 Aug 2013

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Normal MOSFET handling/current limit...interesting. I don't really know what normal current limit for MOSFET is. I am really interested inlearning about it if someone is willing to help. @TZAdvantage: Thanks for the clarification, that was helpful.

smt assembly Edited by dergi 2013-08-13

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