Yes. You are 100% right. On my drafts only the principle is reflected. The protection devices are not shown there. Moreover, a low voltage alarm will be a good idea.upsss wrote:As far as regulating the 3.3V supply directly from the Li-Ion battery, it is a bad idea. Draining a Li-Ion battery down to 3.0V or even 2.8V is perfectly acceptable...
Absolutely NOT!upsss wrote: Regulating the 3.3V supply directly from the Li-Ion battery as you are suggesting, your new LDO 3.3V regulator will stop regulation under worst condition with battery voltage of 3.6-3.7V,
See the regulator's datasheet. Moreover, I tested XC6203 in practice. It works normal down to 3.3 volts, and then just repeats the input voltage.
Using the proposed design, you can double this time (or so). Is it so hard to believe? I never publish unverified things. (My practical implementation has been tested. The circuit solutions are somewhat redundant [in terms of the number of components], and, moreover, are assembled on the DIY PCB. So I do not publish it here).upsss wrote:BTW, my DSO runs with my 1340mAh battery for about 4.5 hours...