From: ken s. <ken...@gm...> - 2006-11-08 15:42:33
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On 11/7/06, Jesse Welling <jes...@gm...> wrote: > So it's not good to power a robostix with a 7.2 lipo then? > That's what I was planning to do but....no go? The robostix regulators are Micrel 5219-5.0 in MSOP-8. You'll have to read the data sheet section "Thermal Considerations", starting on page 8. If you are just powering a robostix, its maximum input at V_ROBOBATT is 12v. If you have anything connected to V_BATT, you must consider the thermal limit of the regulator. Page 10 of the regulator data sheet has an example that shows: operating at room temperature with maximum continuous output current (500mA) requires an input voltage no higher than 5.68v. --- Ken > > > On 11/7/06, ken staton < ken...@gm...> wrote: > > > > On 11/7/06, Dave Hylands < dhy...@gm...> wrote: > > > Hi Ken, > > > > > > > > Since the robostix will often be powered from batteries, and V_BATT > > > > > can't exceed about 6v, the power jack on the robostix is called > > > > > V_ROBOBATT, and it goes through a 5v regulator to become V_BATT. > This > > > > > allows a 9v battery to be used to power the robostix & gumstix. > > > > > > > > pictorial view... > > > > > http://pubs.gumstix.org/documents/Powering_a_Gumstix.pdf > > > > > > Ahah. I see the spec has been changed to 6v now. It used to be > higher.... > > > > I wouldn't call it a spec. > > 6v applied to V_BATT should be viewed as a maximum value. > > Damage will occur if V_BATT exceeds 6v. > > > > V_ROBOBATT maximum becomes a thermal issue that > > depends on the V_BATT load you present to the robostix... > > > > --- > > Ken > > |