Switched-capacitor charge pump
Inverter or doubler with slow-switching charge-transfer resistance and explicitly entered switch-path resistance.
Development preview. Check the assumptions below before relying on a result. Calculations run in your browser.
How it calculates
Assumptions
- Single-stage ideal 1:−1 or 1:2 charge transfer; Rout = 1/(fs Cfly) + entered equivalent switch/ESR resistance.
- The resistance sum is a conservative interpolation between slow- and fast-switching limits, not a switched transient solution.
- Refresh count affects output ripple only. A two-phase interleaved topology needs its total equivalent flying capacitance and switch resistance entered explicitly.
Worked example
These are the calculator's default inputs. Change any input above to recalculate.
Inputs
- Conversion
- invert
- Input voltage
- 5 V
- Load current
- 0.02 A
- Complete charge/discharge cycle frequency
- 100000 Hz
- Effective flying capacitance
- 0.000001 F
- Effective output capacitance
- 0.00001 F
- Equivalent switch-path output resistance
- 5 Ω
- Equivalent capacitor ESR contribution
- 0.2 Ω
- Input quiescent current
- 0.0001 A
- Output recharge events per full cycle
- 1
Results
- Loaded output voltage
- -4.696 V
- Ideal output voltage
- -5 V
- Equivalent output resistance
- 15.2 Ω
- Capacitive output ripple
- 0.02 V
- Flying-capacitor voltage swing
- 0.2 V
- Modeled conversion loss
- 0.00658 W
- Modeled efficiency
- 93.4527 %
- Average input current
- 0.0201 A