Curtis Heisey <[email protected]> writes:

> I hooked a LiPo 2s Batttery to my TeleMetrium, and smoke poured off
> the bottom.

Ouch!  Sorry to hear that.

> Then I revisit the manual, which talks about 1S LiPo but
> does not seem to mention a max supply voltage for the TeleMetruium.

Well, that's because TeleMetrum is not designed to work from arbitrary
power sources.  The design is specifically intended to work with a 1S
LiPo.  This is because the board includes a LiPo charger, the MCP73831,
which takes current from USB to charge the battery.  This chip really
doesn't like operating with anything other than a 1S LiPo attached to
its output, and is usually the first thing to smoke when you hook up the
wrong type of battery to a TeleMetrum (or TeleMega, EasyMega, TeleGPS,
etc). 

Given the design decision to include an on-board 1S LiPo charger, we
then picked the LDO regulator that had the lowest drop-out (board keeps
working until the lowest possible battery voltage for longer run time)
that had an adequate input range to handle a fully charged 1S LiPo.

So, yes, I guess we could be explicit about the voltage range the LDO
on our products can handle, but that wouldn't change the fact that only
a 1S LiPo is supported.

The one big exception to this is EasyMini, on which we used a different
voltage regulator that can handle a wider range of inputs, specifically
to allow use of 9V alkaline cells which are important to customers in
the low-cost, baro-only, dual deploy market segment. 

If you want to fix the board yourself, expect to have to replace both
the LDO and the LiPo charger.  The board is likely to be just fine
otherwise.  If you'd like me to fix it for you, email me the board
serial number and I'll open an RMA for you. 

Bdale

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