Artlav
Full Member level 2
Ok, some simplifications and part cross-referencing later i got a proof of concept for the charge pump:
The flip-flop consumes about 6μA, the switch side consumes less than i can measure.
From 1.5mA at 0.45V this gets about 250μA (at 1V) and up to 3.3V of raw output, and is quite capable of maintaining itself once the big capacitor is charged over 2.4V.
I haven't tried to optimize the design yet - frequency (~70Hz) or capacitor sizes might be way off optimal.
Also, the power leaks out if the source voltage drops - needs a diode between the last stage and the big capacitor.
Any obvious improvements?
At the least i'm looking for some kind of a sub-μA oscillator at ~100Hz to drive it.
The flip-flop consumes about 6μA, the switch side consumes less than i can measure.
From 1.5mA at 0.45V this gets about 250μA (at 1V) and up to 3.3V of raw output, and is quite capable of maintaining itself once the big capacitor is charged over 2.4V.
I haven't tried to optimize the design yet - frequency (~70Hz) or capacitor sizes might be way off optimal.
Also, the power leaks out if the source voltage drops - needs a diode between the last stage and the big capacitor.
Any obvious improvements?
At the least i'm looking for some kind of a sub-μA oscillator at ~100Hz to drive it.