pnoyes wrote:
EDIT: Just to follow up:
The Display from the Datasheet pulls a max of 90mA at 3.3v (so 60mA from the 5V perspective) but it is not run at full brightness so it consumes less.
The RAM and ROM pull far less than 40mA each because they are clocked at 1MHz. Current consumption is related linearly to clock speed and those current limits are spec'd for the maximum supported clock speed which is an order of magnitude higher.
Thanks for that. I had not considered that, of course, the RAM/ROM will draw less current at less than their maximum specified clock speed. I do a lot of not quite thinking things through! As to the screen, the nearest equivalent I could find to what you're using (there's no part numbers so I'm going by physical looks of the screen) says it draws up to 310mA, so I'd be interested to know what screen you're using.
A further note, I believe that the 1N4148 diodes in your debounce circuit are unecessary. The circuit you've used is a direct lift from
here, which on the matter of the diode states:
Quote:
The diode is an optional part needed only when the math goes haywire. It's possible, with the wrong sort of gate where the hysteresis voltages assume other values, for the formulas to pop out a value for R1 + R2 which is less than that of R2. In this case the diode forms a short cut that removes R2 from the charging circuit. All of the charge flows through R1. The previous equation still applies, except we have to account for drop across the diode. Change Vfinal to 4.3 volts (5 minus the 0.7 diode drop), turn the crank and R1 pops out.
However, R1 + R2 is obviously greater than R2 in this case. Further the R1/R2 values are those from earlier in the article, and do not take into account the diode (Vfinal = 5V not 4.3V) so it may actually be suboptimal to have the diode in place.
It is identical to the 2.4" 128x64 OLED module that Adafruit sells except for the color.
Thanks for the tip on the diodes. I will dig into that to make sure I am doing it the right way!
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