I want to design a suitable PCB for my audio amplifier project. The amplifier boards (both left and right channels) will use almost 4 amps at 24 V at full power. I want to use a switch mode based power supply brick (like a laptop charger) that is rated at 6 amps, 24 V but am concerned about the inrush current this power brick will face charging two 22000 uF capacitors at power on.
I'v done a little research and have found a NTC thermistor with a relay shorting the thermistor out over a time period is a common solution to this problem, so I used Falstad to simulate as best I could.
Note: the 5 ohm resistor is in place of the NTC thermistor as the simulator dose not seem to have one.
The 6 ohm resistor emulates the amplifier load.
The PNP transistor to the left is to discharge the 470 uF capacitor as soon as the circuit is powered off to 'reset the timer'.
Note: the 5 ohm resistor is in place of the NTC thermistor as the simulator dose not seem to have one.
However the load on the power brick still has a sharp peak of over 50 amps! is this accurate? (due to capacitor ESR ect..) and will my power brick handle such a spike?