Hello Gaston, > Jens, > David gave you sound advice. A voltage regulator fitness for a > given task is not only related to precision. It also has to do among > other things with repeatability (its ability to reach a voltage every > time it is started),
Yes, but I have measured the voltage several times to check and it was "stable" 4.99V, at least on my multimeter. and what I think could be generating problems to > you, regulation as a function of the load. We are talking of 10 bits, > what means we are talking of ~5 mV per bit full scale assuming 5 volts > full scale. I think that if for some reason you don't want to use the > internal ref (I can't imagine why, but I'm not in your shoes), then > you can always use some cheap reference or shunt regulator like the > venerable TL431. Thanks for the tip. I am using the MAX1242 ADC from Maxim. I also have the MAX1243 here that does not have an internal reference. So I will think about the TL431 when using the MAX1243, thanks! > Also, be very careful with the ground layout. This things are > disturbed by the movement of a mosquito wing ;) Thanks for the tip. The problem is that I am not a professional engineer, I have "learned" my stuff by trial and error, since I have never had a real teacher for electronics. This semester at the university I will take a course called "electronics", and if it is any good, it will be the first time I learn something correctly about electronics. I have also never used ADCs before, so this is my first project with them. The voltmeter I have built is a prototype for the final voltmeter that I would like to build into an adjustable power supply for my Nixie tubes. I am not planning on designing a PCB, all I do is solder the components on my board and then wire them manually on the back. I am afraid that reasonable "ground layout" is not really possible with this technique. But since I only need an accuracy of about 1V, it is quite OK what I achieved with this "babaric" solution ;-) I hope I will get the schematic and some pictures of the board online soon, I bet you guys see a lot of things that can be improved. All the best, thanks for your thoughts, Jens > On Oct 12, 4:46 pm, Jens Boos <webmas...@jb-electronics.de> wrote: > > > And another follow-up: I realised my offset was in fact a linearity > > error, so I tweaked a little bit, and a correcting term of 0.004 / Bit > > did the trick. Is this ethical? ;-) > > > Jens -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to neonixi...@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
