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The PlayStation 4 Pro and PlayStation 5 have orange, blue and white leds to indicate the status of the console.

Boot - Blue

Idle - White

Rest - Orange

The PS4 Pro / PS5 leds and their transistors are on a separate pcb connected by a 6 pin ribbon cable.

What I want to do is replace the white and orange leds with red and green so that I can output any color of my choosing at each state. To do this i'm guessing I need some kind of micro controller pcb programmed with a custom script. To be placed between the PlayStation motherboard and the led pcb.

Technical Details:

  1. The leds are always connected to 5v.
  2. Each led signal goes to the base pin of an unknown model transistor .
  3. When each led is fully on the transistor base pin gets 3.3v and 450 microAmps.
  4. When the led pulses it goes between 0-3.3v and 0-450 microAmps on the transistor base pin.

Obviously I need to emulate the signal each transistors base pin is expecting with the micro controller.


Example:

Lets assume the leds are now:

Boot - Blue

Idle - Green

Rest - Red

So if I want my idle state led to be purple (R+B=Purple) I need to tell the micro controller when it sees a 3.3v 450 microAmp signal on the idle led input pin to output a 3.3v 450 microAmp signal on both the blue and red led transistor base output pins.


Does this sound like something that can be easily done with readily available cheap micro controllers, if so what would you recommend?

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Your question is formulated with some ambiguity. Therefore, I'm trying to come up with an answer whilst stating my assumptions.

(1) Assumptions: The LED-PCB is connected and driven in the original PS4/5 as follows:

schematic

simulate this circuit – Schematic created using CircuitLab

  • The LED Signals are PWM modulated to control the brightness (Sig_A - Sig_C).
  • The logic Signals are not inverted (Sig_A = 1 == Led_A = 1)

(2) Problems:

  • The first problem is, that the Front-PCB does not have a continuous 3V3 logic-supply. Therefore, the uC to convert the signals is not always powered on!

  • The LED-Signals are driven LOW via an NPN - otherwise they are High-Z.

  • I'm guessing, that the 3V3 Lins are driven activly also. Otherwise, a 4-Way Ribbon would have been used most likely (Cheaper).

(3) Solution:

schematic

simulate this circuit

  • You'll need to connect a continuous 3V3 and GND cable within your PS4/5 to make this possible. You can use some standard wire and solder it to the Main-PCB.
  • You then can use a uC to sense the Signals (Caution: Logic is inverted through the Pullups) and make sense of them within Software (Measure PWM Value). The LEDs you want to use are driven bei the uC directly.

(4) Notes:

  • You can use either a cheap Micro (Atmel AVR, PIC, .... ) or an CPLD/FPGA (Xilinx e.g.)

  • You'll need to design an PCB

  • Programming the uC in (C or C++) sounds easy at first, but you'll have to do some advanced stuff to decode the PWM values correctly and generate the three PWM signals for the LEDs.

  • You'll need to solder to the main PCB of the PS4/5 which can damage the unit.

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  • \$\begingroup\$ The separate PCB contains the leds, their transistors and the always on 5v. \$\endgroup\$
    – finalman
    Jul 16, 2023 at 21:10

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