Peak detector and sample hold
Peak detector and sample hold with circuit equations and operating-limit checks.
Development preview. Check the assumptions below before relying on a result. Calculations run in your browser.
How it calculates
Droop: ΔV = Ileak thold/Chold
Acquisition estimate: tacq ≈ max(C ΔV/Imax, ΔV/SR) + RC ln(1/error)
Charge injection: ΔVQ = Qinj/Chold
Assumptions
- Positive leakage discharges the hold capacitor. Acquisition sums a large-signal charging interval and a linear RC tail, providing a conservative screening estimate rather than an exact driver model. Dielectric absorption, comparator/diode recovery and leakage temperature dependence are omitted.
Worked example
These are the calculator's default inputs. Change any input above to recalculate.
Inputs
- Hold capacitor
- 1e-7 F
- Total signed leakage current
- 1e-9 A
- Hold interval
- 0.1 s
- Acquisition step
- 1 V
- Charging source resistance
- 100 Ω
- Maximum charging current
- 0.01 A
- Driver slew rate
- 1000000 V/s
- Acquisition accuracy
- 0.1 %
- Switch charge injection
- 1e-12 C
Results
- Hold voltage loss
- 0.001 V
- Conservative acquisition estimate
- 0.0000790776 s
- Droop rate
- 0.01 V/s
- Charge-injection step
- 0.00001 V