Thread: Fusion Brain Version 6 -- Beta Testing

Originally Posted by rEegLer

Do you have the .ICO file for FuseGL? It's not showing up in XP and I'd like to have something for it.

For the system tray, or you do you mean the icon on the exe itself?

Sorry, I meant the icon file for the exe

Can you explain why there is a voltage present (~10.8V with a 13.2V input) between ground and the sinking side of any digital output? I'm interfacing the FB with my PIC controller using the sinking side of the digital outputs but there is a high voltage present when the outputs are off.

Originally Posted by rEegLer

Can you explain why there is a voltage present (~10.8V with a 13.2V input) between ground and the sinking side of any digital output? I'm interfacing the FB with my PIC controller using the sinking side of the digital outputs but there is a high voltage present when the outputs are off.

It is a less than a milliamp of leakage through the NPN Darlingtons. If you are interfacing with something I would suggest replacing the NPN's with FETs. I actually have 2 spare FET prototypes with them all replaced with NFETs already. We could work something out if you are interested in those. Otherwise, to minimize the leakage (you can never fully prevent it) pull the NPN gate to ground through a few K resistor.

Another solution if this will all be in the same system all the time, then power the FB with the same VDD as whatever else you are using. Then pullup the inputs to the same VDD through a resistor. Any imbalance will be taken out. Then when you turn on the output, the current through the pullup in sunk and the input node is very close to ground (def below TTL low).

I just un-soldered one of the LED's and that solved it for me. I don't understand how there can be leakage through a NPN Darl. transistor when I was just measuring between the emitter and collector.

Something else that is strange; I don't want USB to EVER power the FB because I put my CarPC to sleep and USB stays powered during sleep state, so I made a USB cable that doesn't have the 5V line. Even with the FB powered externally my computer will not pick it up. If I plug my V4 into the same cable, it works fine. Any idea?

Originally Posted by rEegLer

I just un-soldered one of the LED's and that solved it for me. I don't understand how there can be leakage through a NPN Darl. transistor when I was just measuring between the emitter and collector.

Unsoldering the LED is another solution to a different problem. You have VIN -> R -> LED -> Floating (where you are measuring). So you are going to get VIN - diode drop on the floating. But it shouldn't really be floating, it should be pulled up if you are interfacing to something.

Leakage through the NPN is common and does happen. Remember they are bipolar devices, not fet devices. A very small amount of current at the base, turns it on slightly. The way the circuit is, it will never be 100% off, but it will be very close. So that little bit of current at the base, makes current flow through it.

Originally Posted by rEegLer

Something else that is strange; I don't want USB to EVER power the FB because I put my CarPC to sleep and USB stays powered during sleep state, so I made a USB cable that doesn't have the 5V line. Even with the FB powered externally my computer will not pick it up. If I plug my V4 into the same cable, it works fine. Any idea?

USB staying powered should be solvable in the BIOS.

But anyways, you can't just cut the power line for USB. It is used to detect when USB is connected along with the data lines. You need all 4 USB lines going to the FB. If you don't want it powered via USB, then you need to remove either the USB protection diode or the thermal fuse which will disconnect it from the buck circuit but leave it connected to the MCU.

Originally Posted by 2k1Toaster

USB staying powered should be solvable in the BIOS.

Sadly it's not. There is no power option in the BIOS for it. I talked with ZOTAC tech support and they say there is no way to do it on my board. There's also no physical jumper (sometimes common) to enable/disable it.

But anyways, you can't just cut the power line for USB. It is used to detect when USB is connected along with the data lines. You need all 4 USB lines going to the FB. If you don't want it powered via USB, then you need to remove either the USB protection diode or the thermal fuse which will disconnect it from the buck circuit but leave it connected to the MCU.

I just made a little relay circuit that enables the +5V line when ignition is on. Thanks for the reply.