An RC charging based Soft-Start circuit for Voltage Regulators

A soft-start circuit for linear voltage regulators based on slowly ramped-up reference voltage is presented. The proposed circuit prevents overshoot in regulator output voltage without affecting regulator amplifier loop. The proposed circuit does not require external reference voltage or current to generate a slowly ramped-up reference voltage. It has been designed in 5nm FinFet technology for a temperature range of −40°C to 125°C and supply voltage range of
$1.8V\pm 10\%$
. The simulation results show that the proposed soft start circuit reduces the peak overshoot voltage by 30% and consumes only
$10\mu A$
quiescent current.