12/14/2020 at 14:38 •
Survey on USB-C cables
I checked several USB-C cables concerning voltage drop.
I set my electronic load to 2A and switched the Supercap Pi USV on with charged capacitors.
Keep in mind that if they are empty, the charge current of 1A adds to the 2A!
This measurement again shows that the only good supply solution is to use the official Raspi 4 power supply.
Cable Type length Voltage drop Orzly® Neue Zertifizierte USB 3.0 Kabel (Amazon) 1m 340mV Xaomi Mi9T pro cable 1m 610mV USB Typ C Kabel, RAVIAD (Amazon) 0.5m 420mV USB Typ C Kabel, RAVIAD (Amazon) 3m 650mV Official Raspberry Pi 4 USB-C supply 1.5m -70mV (Voltage at USB-C connector
of the Supercap Pi USV was 5.07V)
11/24/2020 at 17:37 •
Perfect replacement for the 35F EATON Supercaps
Vishay has automotive qualified supercaps with 30F capacity.
AEC-Q200 Vishay 225 EDLC-R SuperCap, radial 30F -20 %, +50 % / 2.7V, Ø 18.5 Dia. x 27mm
Lifetime 500000 cycles, >10 years at 20°C.
They fit perfectly onto the board and do not interfere with LAN & USB of the Raspberry Pi.
11/24/2020 at 11:19 •
Relay expansion is available on OshPark for DIY