You COULD use a linear regulator if you have a large enough heatsink because any linear regulator will dissipate lots of heat.
Whether the voltage would be stable and sufficiently clean depends on the circuitry you put around the regulator.
I wouldn't use a linear regulator switch mode power supplies are preferable.
PS I don't know why you would want to ...
You can power any Raspberry Pi via the 5V pins on the pinheader (Pin 2 + 4) or by soldering to the testpads (Tp1/Tp2/Tp3). Be aware that the pinheader is unfused and that you need to provide regulated 5V at up to 3A to the RPi4. You should use minimum 24AWG/0.2mm2, preferably thicker gauge wire, especially if wires are long.
I have soldered wires directly ...
The best option is a good quality power supply, as cheap brands may
say they are rated at 2.4 amps when they don't actually supply that
much. Based on the numerous bad experiences I've had with 3rd party
chargers, I'd highly recommend buying the official one from the
Short answer: Looking for a 5V / 3Amps power supply, not the ...
Look into the Specs section:
PowerIQ Output: 5V=6A(2.4A Max Per Port)
USB PD Output: 5V=3A/9V=3A，15V=2A/20V=1.5A
Strictly speaking, you can power two Raspberries from USB-A ports (marked IQ), and another one from the USB-C port (marked USB PD). This includes any external USB devices you attach to them. Since it's quite unlikely that all Raspberries ...
DO NOT connect a "variable power supply" to the Pi! Most (laboratory grade supplies excepted) are poorly regulated.
DEFINITELY DO NOT connect any power supply to the 5V rail of a powered Pi. (It is acceptable to power the Pi through the Header pins - provided the power supply meets the Foundation recommendations.) Your confusion between series/parallel is a ...
All the advice I have seen says no. Use the Pi's power supply via the microUSB or use your own power supply via the 5V and ground pins. If you use both they will "fight" with each other and cause problems.
Why not power your external kit with the external 5V supply? You can still share the grounds if the external kit has logic which needs controlling ...
I searched and found this link:
I think it's your charger/power bank. As you can see on the description on the device and the link, the output is 2.1A (2.1 Amper) at 5V (5 Volt DC).
On the other hand, "The Foundation's" published figures for power consumption across all models of ...
As stated in the Raspberry Pi Model B specifications found here,
the "minimum*" current for the Raspberry Pi 4 via the USB-C connector and GPIO headers is 3A. (* being a "good quality 2.5A power supply can be used if downstream USB peripherals consume less than 500mA in total.")
Also, in the answer to this question, the user states that while 3A is "...
In general chargers do a poor job of providing a well regulated 5V output - you need a Power Supply
No one can say what your unidentified charger does, but if it has a USB2 output it will probably not work.
A USB-C power unit MAY work, but even this varies.