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Simplify Charge Pump and Depletion Mode FET
U4
Original parts
Charge pump switch regulator
Depletion mode FET
New Change
Find closed switch to replace the two components
Part requirement
Normally closed relay
Support
151.5V + safety factor
0.5A
Controllable
Can close on-demand or
Closes when car close
Implementation
Remove
Charge pump and corresponding capacitors
Pull-down resistor
Keep
LED and resistor
Current limiting resistor
Solid-state relay
https://www.digikey.ca/en/products/detail/ixys-integrated-circuits-division/PM1206/654953
600V and 0.5A
AC
https://www.digikey.ca/en/products/detail/ixys-integrated-circuits-division/CPC1963G/2417218
600V and 0.5A
AC
https://www.digikey.ca/en/products/detail/panasonic-electric-works/AQZ204/646377
400V and 0.5A
Datasheet below
https://www.mouser.ca/ProductDetail/Panasonic-Industrial-Devices/AQZ204?qs=Wn4D5qJAqBLvGIN%2FDTrEgw%3D%3D (mouser link)
Preferring this one?
Smaller changes
Removing:
Fan control
Remove fan connector
Remove entire fan control sheet
Thermistor
Remove thermistor connector
Remove entire thermistor sheet
Add jumpers near AND gate to skip it
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