Boost voltage

[Claudio L.]

(06-06-2015 02:29 PM)Tugdual Wrote:  Thanks Claudio. This means we can operate safely until about 1V which is aligned with the video and is a very good news. Do you by chance know how the battery indicator reacts to voltage?

I completed a test run with NiMH rechargeables and my own "safe" battery warning values. With the calculator continuously "on", running at 6 MHz, this morning the battery indicator started showing continuously (asking me to change the batteries). Once the indicator shows, the calculator locks the slow mode to prevent failure, so we should assume current stayed at 12 mA more or less throughout the test.
On light use but without turning it off for a couple hours, the battery indicator finally went critical (blinking), and almost exactly one hour later the calculator began resetting itself in a loop.

That's what my "safe" voltages will get you: a couple of hours of operation at slow speed, and then about one hour more once it goes critical.
Now I don't think these voltages are so "safe" anymore, perhaps I need to raise them a little more.
Later, I will measure the voltage (with no load, as the calculator can't function) on these batteries and report back. This will be the reference voltage for "fully depleted" batteries.
Stay tuned.