Hi all. I've (embarrassingly) sunk dozens of hours into this project, but am none the wiser. I was hoping some of y'all could help me.
I want to build a clock using a microcontroller that gets time from WiFi (or ethernet?), has a RTC backup, and then displays the time and date on a vacuum fluorescent display. I have no idea what board to get, but I was going to get these other parts:
The problem I'm having is that the displays require 5v. And I have no idea what the best way to power it is. The power draw seems much to high to just use a usb with an arduino and then power the vfd via the arduino 5v pin. Moreover, the input for a lot of the arduinos for non-usb is like 9v or so. So overall I'm just super confused on how to best power things.
I checked the specs on the 2nd display and it requires 5VDC at 400 mA. That may or may not be possible depending on the board you select. Since you are planning on powering the board via the USB port, a simple splitter will be more than abe to supply the display and the Arduino.
Do NOT even think about using a 9V smoke detector battery. Either plug the USB to a wall wart or a Lithium power pack from Anker or equivalent.
This would be a great time to take a break and get a copy of the Arduino Cookbook, skim it cover to cover and stop on what interests you. You will find most of what you need with schematics, code and an explanation. Pay attention to the ESP processors as they have radio receivers that will allow you to get NTP without another module and mostly they are not that expensive.
A clock with a display that uses 400mA is not really suitable for battery as power supply. Recharging on a daily basis seems pretty unhandy to me...
There are displays that can run with a few mA (LED) or even less (LCD).
That's not the case. You can power them with 5V through the 5V pin (assuming they are 5V Arduinos). But this feature isn't always mentioned because if the PSU isn't regulated, the Arduino could be easily destroyed. Many beginners don't understand the difference between regulated and unregulated PSU, and could easily damage the Arduino because of their ignorance but then try to blame Arduino, claiming that a "beginner friendly" board should not be so fragile.
Which most Arduino with WiFi are not... they are mostly 3.3V. So it may be necessary to use signal level shifters between the Arduino board and the display. On the positive side, many 3.3V Arduino can be powered with 5V because their Vin pins can take 5V sand regulate that down to 3.3V.
Start with something less ambitious if this is one of your first projects, for example a clock with an LCD1602 display (3 volt version) and an ESP32 development board. Get that working then add features like an RTC backup etc. You can then use some of the components for your next project.
In parallel, google this site (or even more generally) for VFD clock projects of which there are plenty. There you may get an idea of the challenges you'll encounter.
I am not necessarily planning on powering the board via USB, and I am definitely not going to be using a smoke detector battery (?). Also the datasheets for the Noritake mention that "The inrush current at power on can be 2 x ICC." Meaning, the inrush can be 800mA at power on.
So I suppose USB power might actually work in the case of the Noritake display. Conversely, the power-on current for the NewHaven display can reach up to 4.35 amps. So that's way over.