Project description

When I used satshakit that I have build In another extra-project I found 2 points that was disturbing for me.

  • Satshakit, if we use for example FTDI will work on same voltage that I deliver to it (so 5V in case of my FTDI). And in some cases I require 3..3.3 volts to work with connected devices that requires this voltage (esp866 in my case).
  • I have a power IN on board, but I have no power out pin. So I always need to take care of alimentation of my devices.
  • I will add few points to current schematic of Satchakit to have possibility switch it from simple external voltage (mostly 5V) to 3.3V. and I will add the output VCC and GND pins.

    As well I will add global GND to increase surface of ground field.


    adding components to schematic
    Hear 3 pins
    I add the header with 3 pins (central will be IN power and one jumper that we could place on 1,2 or 2,3 pins will permit us to switch between not-modified voltage and regulated to 3.3V)
    Header 2 pins
    Output voltage, same as current voltage of Satshakit, can be used for external devices
    LDO 3.3V
    Regulator voltage, that connected to one of position of IN switch
    Schottky diode
    Diode that will not permit to go from non regulated voltage to regulated part when regulated part is not active.
    Polygone GND
    Added a polygone around the board to propagate the ground on maximal surface.

    Let see what it be


    Standard preparation for Rolland SRM-20 and milling. Images for holes, traces and cutout are below

    I pass to milling and here is result.

    Ready for soldering and usage.
    Now I could develop for my MAX30100 without 3 disconnection of cable each time I want to pass from programming to reading data... It was really borring process.