omega0684
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| posted on 24/1/11 at 01:25 PM |
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12v to 5 v resister?
Afternoon all,
the oil pressure i need to use for my digi dash only requires a 5v supply. The connector has 3 terminals, one for the 5v supply, on to earth and the
other connects to the digidash via an analog input.
how do i control the voltage travelling to the sensor from the 12v ign supply, i'e what resister would i/do i need?
oh, and where can i get one from? Do i just connect the resister in series to the power supply wire connected to the wire?
All the best
Alex
I love Pinto's, even if i did get mine from P&O!
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Madinventions
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| posted on 24/1/11 at 01:31 PM |
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I don't thank that a resistor is the ideal way to do it. You need a '3 terminal regulator' such as a 7805 which will reduce the 12V
down to +5V. The 3 terminals are +12V in, +5V out, and ground. The 7805 can supply a current of around 1A. I've got a box full of them if
you want me to post one up to you?
Ed.
[Edited on 24/1/11 by Madinventions]
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omega0684
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| posted on 24/1/11 at 01:44 PM |
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ed u2u sent
I love Pinto's, even if i did get mine from P&O!
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stevebubs
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| posted on 24/1/11 at 03:50 PM |
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Surely be easier to get a traditional oil pressure sender that enables the Digidash to measure resistance to ground, thus requiring a single wire?
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MikeRJ
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| posted on 24/1/11 at 04:22 PM |
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quote:
Originally posted by omega0684
Afternoon all,
the oil pressure i need to use for my digi dash only requires a 5v supply. The connector has 3 terminals, one for the 5v supply, on to earth and the
other connects to the digidash via an analog input.
Surely if this sensor is the one required by the digidash, the dash would provide a 5v reference supply for it?
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martyn_16v
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| posted on 24/1/11 at 05:07 PM |
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What Mike said. If there's a difference between the actual voltage output from your external 5V source and the dash's internal 5V
reference then the reading the dash tells you won't be entirely accurate (although to be fair it'll only be out by a % or two which is
probably moot for most users).
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plantman
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| posted on 24/1/11 at 06:27 PM |
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ring digi dash up they were brill when i couldn't get my revometer to work had to use 1k resistor told me exactly how to wire it etc
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britishtrident
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| posted on 24/1/11 at 07:08 PM |
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Might be able to tap a 5v supply off some of the other sensor on the engine (eg throttle position sensor)
However I would probably cannibalise a cigar lighter to USB converter rather than build from scratch.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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