This is a
design PCB unit to support everything. This circuit is of course one of the main things on there is the micro.
I am currently using the STM32F4 discovery board that has the 100 pin
STM32F407VGT on board. Since this basically has everything that I need I
decided to simply use that to keep it simple. This is the figure of the
schematic.
We know that ARMs are a bit more complex so
that's why this circuit is asking for help. or now we need a basic circuit that
uses internal oscillators and needs as little hardware as possible (but will
still work reliably). And we want it to be programmable using the SWD
connector. Using different forums and the original datasheet I've come up with
the circuit in the attachment. Is this OK
or do I need anything else?
The data sheet mentions a 4.7uF capacitor on
one of the power lines but I am not sure if this means that I need a 100nF
capacitor and a 4.7uF one or just the 4.7uF. we are also not entirely sure
about the VREF+ capacitor either. What
else do I need if I want to use the internal RTC? Probably something connected
to the VBAT pin? The datasheet mentions a power switch but I don't get how
that's supposed to work. This article is based on roli’s blog in eevlog.com
