so far i have the components and i am on my way to migrate (luckily provided from manufacturer, some quite complicated command sequences) the arduino code to espruino
the final goal is to run from battery, for this i would be thankful if someone can answer my questions
my take on power consumption
assuming 2s operating time every 5 minutes (its a word clock, update every 5 minutes is enough for me), 24s per hour
Pico deep sleep needs 0,02mA/h
Pico operating needs 32mA/h
Display operating needs 8mA/h (but it is an e-paper, power is only needed to update the display, content stays after that)
Pico current draw in mA/h = 0,23 mA/h = (0,02mA/h:3600s*(3600s-24s)) + (32mA/h:3600s*24s)
Display current draw in mA/h = 0,053 mA/h = 8mA/h:3600s*24s final power consumption ~ 0,29 mA/h
assuming 1900mA/h from 2x AA eneloops (2.4v)
according to the specification the display works from 1.9v - 3.3v
operating time ~ 0,76 years = (1900mA/H:0,286533333 mA/h:24h:365d)
i know that is just a theoretical value, voltage drop will probably happen earlier
Questions
Is my take on the power consumption correct?
Are 2.4v enough to drive the pico?
Is it possible to control the VBAT Pin to only activate at designated timer?
So far i think i need a transistor, but maybe it is possible without an extra component.
Are there alternatives to my approach? (can a GPIO pin drive the display? i am not sure about the current draw)
updated
was 2s operating time per hour, but should be (60min/5min)*2s=24s
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
i am an absolute beginner (and even worse with an enterprise programmer background) and thankful for every hint and critic :-)
for my version of a word clock i am trying to use an e-paper display with an espruino pico
the display is this one: http://smart-prototyping.com/NOA-Labs/E-ink-E-paper-new-version-display-module-3.3V-2.04-inch-177x72.html
so far i have the components and i am on my way to migrate (luckily provided from manufacturer, some quite complicated command sequences) the arduino code to espruino
the final goal is to run from battery, for this i would be thankful if someone can answer my questions
my take on power consumption
Pico current draw in mA/h = 0,23 mA/h = (0,02mA/h:3600s*(3600s-24s)) + (32mA/h:3600s*24s)
Display current draw in mA/h = 0,053 mA/h = 8mA/h:3600s*24s
final power consumption ~ 0,29 mA/h
operating time ~ 0,76 years = (1900mA/H:0,286533333 mA/h:24h:365d)
i know that is just a theoretical value, voltage drop will probably happen earlier
Questions
updated