Abstract: A computer system having a power supply monitoring arrangement employs a number of comparators for detecting whether or not various supply voltages produced by the power supply for use in the computer are above or below a reference level, or whether an overcurrent condition exists. These detected conditions are used to determine whether or not the power supply should be shut down, or during power-up to determine whether the initialization routine can be started by the CPU. Delays are included to prevent an undervoltage condition from indicating shut down of the power supply during power-up.

Abstract: A switching rectifier power supply circuit has a power MOS transistor connected in series with half of the primary of a center-tapped transformer, and has rectifiers in series with an inductive load on the secondary side. The gate of the power transistor is driven by a pulse source which is pulse-width modulated in response to the load voltage, and also controlled in response to the current through the power transistor. To prevent leading-edge current spikes due to turn-on of the power transistor from adversely affecting the pulse-width modulator, yet allow trailing-edge current spikes due to transformer saturation to be compensated for, an inhibit circuit is included in the control path responding to current through the power transformer.