SBVS012I December 2000 – September 2020 DCP010505B , DCP010505DB , DCP010507DB , DCP010512B , DCP010512DB , DCP010515B , DCP010515DB , DCP011512DB , DCP011515DB , DCP012405B , DCP012415DB
PRODUCTION DATA
The following example shows that increasing the capacitance has a much smaller effect on the output ripple voltage than does reducing the value of the ESR for the filter capacitor.
To calculate the output ripple for a DCP010505 device:
tDIS = 0.0125 μs
τ = C × RLOAD
τ = 1 × 10-6 × 12.5 = 12.5 μs
VDIS = VO(1 – EXP(–tDIS / τ))
VDIS = 5 mV
By contrast, the voltage dropped because of ESR:
VESR = ILOAD × ESR
VESR = 20 mV
Ripple voltage = 25 mV