The "other stuff" you refer to are resistors and capacitors.
Resistors (the rectangles) generally have an R prefix then a number that uniquely identifies that particular resistor in the diagram (and on the physical board). There will be another number (just below the identified in this case) that indicates the value of the resistor.
Similarly for capacitors - they have a C prefix and are shown as 2 horizontal lines with a gap between them.
Wikipedia has an entry here if you want to have a look.
Yea I gotta learn these data sheets!
Thanks for the explanation and the link! Maybe you can shed some light on the below. If not, I will ask the designer. Thanks!
With #1, it appears there are 2 different types of capacitors, any idea why?
With #2, why go back to VCC? I am assuming there is a VCC bus because there is a bunch that go back to VCC. Is this because VDD on the TM1640 isnt used?
With #3, Why the resistors back to VCC?
I can't see how that can work, according to the TMS1640 data sheet
Display mode (8 sections × 16 bits) supports common cathode digital tube output
Same problem as with HT16K33 and MAX6954.
Is it possible this gentleman has managed to find common cathode version of the displays?
One is labelled "104" which means 10x10⁴ pF == 100,000pF = 100nF. This will probably be a ceramic type. The other is labelled 100uF. That will probably be electrolytic type. You may have noticed that they are connected in parallel and you may have read that when capacitors are connected in parallel, their capacities add together. Your question might then be "why bother adding that second capacitor when it's capacity is 1/1000 of the other?". The answer is that the two types of capacitor react to changes in the current/voltage in the circuit at different rates. The ceramic type may have a very low capacitance, but it reacts much, much faster than the other cap. Between them, they can help deal with voltage and current fluctuations of different sizes and frequencies better than either could alone.
They are called "decoupling caps" and they protect the other chips, and the chip they are connected to, from fluctuations in the voltages/currents in the circuit caused by all digital chips. These fluctuations can cause the chips to misbehave in strange ways, if the caps are not there.
It is used, Vss is another way to say "ground"
I'm not sure, but they are shown in the suggested circuit shown in the data sheet, and it's always a good idea to follow the suggested circuit. You can see the 2 caps there also:
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