Status: Active
Owner: Zen & Chris
Requirements
Passthrough 18 V - 55 V (6S lower voltage to 12S upper voltage )
Measure current through hall effect current sensing (without a shunt resistor to minimize losses)
Measures voltage with an ADC
I2C or UART interface
Preference toward I2C, but just pick one of them
XT90 connector for input power and output power
Maximum current passthrough requirements
Max pulsed current 200 A
Max continuous current 150 A
Steps down input voltage to clean 5V and 12V rails
Refer to Nathan’s current power module, photos in discord, for a reference to what this board will be replacing.
...
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/diodestexas-incorporated/AP2127K-1-8TRG1/4470784instruments/TLV73333PDBVR/5022378
Steps down input of 2up to 5.5V -6V to adjustable output of 1V-4.75V to fixed 3.3V
Supplies up to 300mA of current
Typical Application Circuit
...
Adjustable Output Resistors
...
Capacitors
1uF X7R filtering capacitors on input and output
https://www.digikey.ca/en/products/detail/yageo/RC0603JRmurata-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/586967electronics/GCM188R71C105MA64D/7430540
...
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
...