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https://www.digikey.ca/en/products/detail/murata-electronics/GRM1885C2A510JA01D/586986
3.3V LDO
Requirements
Steps down output from 5V buck to 3.3V to power the INA228, which draws 640uA of current
Selected IC
https://www.digikey.ca/en/products/detail/diodes-incorporated/AP2127K-1-8TRG1/4470784
Steps down input of 2.5V-6V to adjustable output of 1V-4.75V
Supplies up to 300mA of current
Typical Application Circuit
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Adjustable Output Resistors
For 3.3V output, 56.2K and 18K resistors are needed
https://www.digikey.ca/en/products/detail/yageo/RC0603JR-0718KL/726725
https://www.digikey.ca/en/products/detail/yageo/RC0603FR-0756K2L/727303
Input Capacitor
1uF filtering capacitor is required
https://www.digikey.ca/en/products/detail/murata-electronics/GCM188R71C105MA64D/7430540
Output Capacitor
At least 1uF X7R capacitor is required for stabilizing and improving transient response
https://www.digikey.ca/en/products/detail/murata-electronics/GRM188Z71A475KE15J/16602144
Feed Forward Capacitor
Datasheet recommends adding 390pF feed forward capacitor for additional stability and reduced noise
https://www.digikey.ca/en/products/detail/murata-electronics/GRM1885C1H391JA01D/586967
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12V Buck
Requirements
Steps down 18-55V to 12V
The 12V rail is only used to power the vtx, which has a 500mA current draw. Ideally, the current limit of the buck converter should be closer to 750mA to be safe
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