POWER REGULATOR CIRCUITRY WITH POWER-ON-RESET CONTROL

Power regulator circuitry is provided for powering loads such as memory element arrays on integrated circuits. The power regulator circuitry may have a regulated power supply circuit and a switch-based power supply circuit. Control circuitry can control the regulated power supply circuit and the switch-based power supply circuit. The control circuitry may include a power supply power-on-reset control circuit. The power supply power-on-reset control circuit may receive a system power-on-reset control signal from a system power-on-reset control circuit. Based on the system power-on-reset control signal and monitored power supply voltages, the power supply power-on-reset control circuit may apply power-on-reset control signals to depletion mode transistors in the power regulator circuitry to ensure that nodes within the power regulator circuitry have defined values during power-up operations.