The diode prevents that the reset-pullup resistor is a load when high-voltage programming. A 1n4007 will do, but is much larger than required. 4r7 (like 4e7) means 4.7 Omh, so quite low. I guess there will be a little less then 1V over this resistor, so 0.25 will just do.
Joep 2009/7/8 Sebastien Lelong <[email protected]>: > Oh, and what about 1N4148 diode ? What's the purpose ? Make sure the circuit > is correctly polarized ? Can a 1N4007 do the job ? > > ... > Seb > > 2009/7/8 Sebastien Lelong <[email protected]> >> >> Hi guys, >> >> I'm currently building the LCD interface board (and by this way will write >> a new blog post). I'm a little confused by the resistance values. According >> to the schematic, R5 is "4R7/0.5W". Does this mean 4.7Kohm or 4.7ohm ? Does >> it really have to be 0.5W, or 0.25W is ok (well I guess this wasn't put here >> randomly, but I don't have a 0.5W resistance, so I wonder if a 0.25W could >> the trick, or if this will result in some smoke...). >> >> >> Seb >> -- >> Sébastien Lelong >> http://www.sirloon.net >> http://sirbot.org > > > > -- > Sébastien Lelong > http://www.sirloon.net > http://sirbot.org > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "jallib" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/jallib?hl=en -~----------~----~----~----~------~----~------~--~---
