Hi,
Due to a brain fart, I mis-connected the power to my arduino NG (a 9v battery). One of the small chips, the power regulator I think, smoked a little before I yanked the wires out. Now when I power it up, I only get about 1.6V off of the 5v pin. I'm hoping that only the regulator was fried. Is it possible to replace the regulator?
Meanwhile I attempted to use the USB power. It does power up and I even see some TX/RX activity. However, windows insists that it is an "unknown device", and won't install the FTDI driver.
Is there any hope, or should I just put this in the "experience paid for" column?
Well I guess it depends how badly you misconnected the 9V battery. The voltage regulator is completely disconnected when the NG is powered by USB, so even a fried regulator shouldn't matter (the USB connection supplies the 5V in this case).
Since yours is not working from USB, I'd have to assume the FTDI chip got hit - although I don't know how you did that. I suppose if you hooked up the 9V battery to the 5V header or to one of the digital/analog pins that might do it. Simply connecting the 9V with reversed polarity to the 9V header should have only damaged the external power circuit (voltage regulator or capacitors).
that sounds fried! The FTDI chip is likely internally melted, and the regulator sees a short circuit, so it only puts out 1.6V as it is in protection mode.