Depends on the battery type. With a primary cell you dissipate some of the = energy in the cell as well. Lithium thionylchloride batteries for example = do not like it one bit. However the standard CR2032 is manganese dioxide in= stead so its internal impedance isn't as severely impaired by large current= draws. =20 I suggest you ignore TI's claims. The main reason why is you should always = go by the battery manufacturers specs. Since you cannot test the batteries = without discharging them and possibly damaging them in the process you cann= ot test and sort for which battery will fail. Bottom line is the batteries = are made to a spec and the manufacturer can change the battery beneath that= spec any time as long as it meets the spec. This happens with rechargeable= lithium ion batteries all the time. Although less likely with a lithium pr= imary cell it's a possibility and your design may not work any longer. Stephen --- On Tue, 11/2/10, Mark Rages wrote: > From: Mark Rages > Subject: [EE] Coin cells and peak current draw > To: "Microcontroller discussion list - Public." > Date: Tuesday, November 2, 2010, 11:43 AM > (Adding tag) >=20 > I have often heard that drawing pulses of more than about > 15 mA from a > CR2032 coin cell will permanently degrade its capacity. >=20 > But TI has done the experiment and claims up to 30 mA with > minimal > change in battery capacity: >=20 > http://focus.ti.com/general/docs/lit/getliterature.tsp?literatureNumber= =3Dswra349 >=20 > Battery internal resistance is still the enemy, though. =A0A > big > capacitor can help hold up the voltage during the current > peak. >=20 > Looks like all testing was at room temperature too, which > seems like a > big limitation. =A0Also interesting is the difference > between claimed > and actual performance. (spoiler: Sony good, noname bad). >=20 > Regards, > Mark > markrages@gmail > -- > Mark Rages, Engineer > Midwest Telecine LLC > markrages@midwesttelecine.com >=20 >=20 >=20 > --=20 > Mark Rages, Engineer > Midwest Telecine LLC > markrages@midwesttelecine.com >=20 > --=20 > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist >=20 =20 --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .