Obi1
08-30-2014, 01:54 PM
After finishing the wiring and workbench tests of my first LED string (http://forums.thecustomsabershop.com/showthread.php?16889-My-first-LED-string-blade-a-progress-diary), I though I would share the wiring I came up with. I got some enquiries how I managed to run a Serial II. type LED string off from ~7.4V (2 x 18650) and using a Hasbro board. Sorry if some of the ideas here were already posted, I went through many of the Hasbro wiring threads, which were invaluable for me as well, and since this adds some new flavors, I though others might also benefit...
It's well known that Hasbro boards (UFX or FX, does not matter which, drive principle being the same) run off from max 5V, but Serial type LED strings need more than that (well, except if it's a Serial II. red...my was a blue one, needing typ 6V). This led me to the idea to use the Hasbro board to control external driving stages. The wiring diagram you see on the pic below, here some explanation:
- 5V voltage Regulator: I used one I became for free :), I wanted one which can deliver somewhere aroud 100mA (although a Hasbro board eats much less than that). The 2 caps on the Input(I) and Output(Q) respectively are recommended (both to include them and the values, although it can vary with regulator type).
- VFVR: please do not go and google for it, it's a name I came up with and stays for Visual Feedback Voltage Regulation. It means: you look at the blade and adjust the drive until you are satisfied with the brightness you see). In principle it's an NMOS with a potmetter connected to the gate. It acts as a drive adjustment, replacing and eliminating the need to use resistors to limit the current to the LED strings (I'm not a fan of resistors...). The Transistor will be fed from the battery voltage, somewhere between 7.4V and 8.4V assuming 2x18650, using the potmeter I can adjust the voltage to the LED string. This has the additional advantage of being able to adjust the brigthness of the blade (not something to be disregarded if you are torn between wanting to have the brightest blade in the Universe and keeping the eyes of your kids and yourself in good working condition).
- all segments work the same way: the output from the Hasbro board (Seg[1] to Seg[n], where n is 6 for an FX and 5 for an UFX) connects to the gate of an nMOS transistor. To ensure that the Transistor Switches off when the saber is switched off, I included a 100kOhm pull-down resistor to GND, but it might be not strictly necessary. The source will connect to GND (I mean battery negative), while the drain will go to the segment cathode (LED-).
http://i1035.photobucket.com/albums/a432/Kunci1/LEDString_Hasbro_HP_zps6c3f4c79.jpg (http://s1035.photobucket.com/user/Kunci1/media/LEDString_Hasbro_HP_zps6c3f4c79.jpg.html)
Additional benefit of the higher voltage is that the very timid UFX board became a sound monster with a TCSS 2W speaker and the 5V from the regulator.
I have some ideas how to implement a blade flash-on-clash and swing flash with this setup, but it's still in the concept phase.
Feedbacks would be greatly appreaciated, and please ask is something is not clear (I hope I did not make any mistake on the wiring,it's already quite late...)
It's well known that Hasbro boards (UFX or FX, does not matter which, drive principle being the same) run off from max 5V, but Serial type LED strings need more than that (well, except if it's a Serial II. red...my was a blue one, needing typ 6V). This led me to the idea to use the Hasbro board to control external driving stages. The wiring diagram you see on the pic below, here some explanation:
- 5V voltage Regulator: I used one I became for free :), I wanted one which can deliver somewhere aroud 100mA (although a Hasbro board eats much less than that). The 2 caps on the Input(I) and Output(Q) respectively are recommended (both to include them and the values, although it can vary with regulator type).
- VFVR: please do not go and google for it, it's a name I came up with and stays for Visual Feedback Voltage Regulation. It means: you look at the blade and adjust the drive until you are satisfied with the brightness you see). In principle it's an NMOS with a potmetter connected to the gate. It acts as a drive adjustment, replacing and eliminating the need to use resistors to limit the current to the LED strings (I'm not a fan of resistors...). The Transistor will be fed from the battery voltage, somewhere between 7.4V and 8.4V assuming 2x18650, using the potmeter I can adjust the voltage to the LED string. This has the additional advantage of being able to adjust the brigthness of the blade (not something to be disregarded if you are torn between wanting to have the brightest blade in the Universe and keeping the eyes of your kids and yourself in good working condition).
- all segments work the same way: the output from the Hasbro board (Seg[1] to Seg[n], where n is 6 for an FX and 5 for an UFX) connects to the gate of an nMOS transistor. To ensure that the Transistor Switches off when the saber is switched off, I included a 100kOhm pull-down resistor to GND, but it might be not strictly necessary. The source will connect to GND (I mean battery negative), while the drain will go to the segment cathode (LED-).
http://i1035.photobucket.com/albums/a432/Kunci1/LEDString_Hasbro_HP_zps6c3f4c79.jpg (http://s1035.photobucket.com/user/Kunci1/media/LEDString_Hasbro_HP_zps6c3f4c79.jpg.html)
Additional benefit of the higher voltage is that the very timid UFX board became a sound monster with a TCSS 2W speaker and the 5V from the regulator.
I have some ideas how to implement a blade flash-on-clash and swing flash with this setup, but it's still in the concept phase.
Feedbacks would be greatly appreaciated, and please ask is something is not clear (I hope I did not make any mistake on the wiring,it's already quite late...)