The issue is still under investigation. If you're curious, here's the thread I've been keeping with TI engineers to try to resolve it: http://e2e.ti.com/support/power_management/non-isolated_dcdc/f/196/p/390774/1379558#1379558. The issue is now believe to be more associated with load (output) switching rather than line (input) switching and has only even been observed with 12V or above. A Zener or TVS would not help you here (you don't have enough margin). The next revision of the IOIO, as soon as this issue is resolved, will contain a simple protection circuit comprising a Zener and a FET that protects the voltage surges. However, this is known to be insufficient (because the failure had been observed with this circuit in place, while monitoring Vin and asserting that it has not exceeded the maximum ratings). One thing that you can probably do in the near term if you have to use 12V input is step-down the 12V to, say, 9V using an external regulator that is more robust.
On Mon, Jan 12, 2015 at 6:57 AM, Andries Kruger <[email protected]> wrote: > Hi all, > > So my VREG finally fried today. It might have been one of two things that > fired the VREG: > 1) Might have happened when I plugged in my phone > 2) Was using a new power supply and might have happened when I powered on > the supply. > > For my applications, I will need to be running from a 12V power supply. I > know the IOIO isn't great with anything more than 10V but I have no choice. > I have ordered a new VREG and will hopefully be replacing this one in a > week or so. > > My questions are: > 1) Can I protect my IOIO with a Zener diode or TVS over Vin? > 2) If this is possible, does anyone know of a nice TVS or Zener with the > best possible spec to do this? > > Thanks. > > -- > You received this message because you are subscribed to the Google Groups > "ioio-users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/ioio-users. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "ioio-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/ioio-users. For more options, visit https://groups.google.com/d/optout.
