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I created this for myself to keep track of things, but feel free to comment and I will add/correct the list.
- Start compiling the headers/housings needed for these connections between the boards.
I have them below, please review at your convenience!
- VTX has built in filter, just remember to add caps at the voltage input to the board.
Will keep in mind during schematic phase.
- Compile the total current required on the 5V and 12V rails.
Max of 224mA on board, will opt for linear regulator over switching
- Source 5V smps linear regulator based on current requirement.
- Can the OSD take 5V directly from the pixhawk from the input header? If so, then we would not need the 12V-5V step down on the board, and we can use 12V for everything: cameras, osd, and vtx.
- Figure out whether or not the board 3 way camera switch board can use the common CAN circuit so we don’t have to use PWM pin.
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1 6-pin JST connector (no clue about the pitch with my search), 1.00mm pitch.
5V Linear Regulator Selection
Two promising ones found on digikey with the following filters: linear regulator, current output: >1A, input voltage max: >15V, in-stock
AZ1117IH-5.0TRG1: AZ1117IH-5.0TRG1 Diodes Incorporated | Integrated Circuits (ICs) | DigiKey
LDL1117S50R: LDL1117S50R STMicroelectronics | Integrated Circuits (ICs) | DigiKey
I am opting for the LDL1117S50R as it provides better line and load regulation based on its graphs with honest 5V output and from 6-18V inputs, while AZ1117IH-5.0TRG1 shows similar behaviour in both categories but only with Vin of 4.5V for its 2.5V output variation and no graphs for line or load regulation for the 5V output component.
Both show very similar behaviour in terms of line and load transient behaviour, with:
AZ1117IH-5.0TRG1: ~60mV max for the line transient and 130mV max for the load transient
LDL1117S50R: ~60mV max for the line transient and 120mV max for the load transient
A bonus is that the LDL1117S50R shows better PRSS of 87dB @120Hz compared to the AZ1117IH-5.0TRG1 with a PRSS of 70dB @120Hz.
Ferrite Bead Selection
Search criteria on digikey: Imax > 500mA given the 224mA max on the board, R @120Hz > 100R, R @DC < 30mR, 0603 package
Final part selected: BLM18SG121TZ1D Murata Electronics | Filters | DigiKey