Buck Variable Negative Current

摘要

An active diode formed within a buck power regulator with an NMOS transistor is connected to a PMOS transistor at a node that is further connected to the regulator output through an inductor. The active diode combines the NMOS transistor with circuitry to prevent conduction once the active diode passes a threshold voltage. Additional circuitry compares the output voltage to the target input voltage and varies the threshold voltage of the active diode such that the active diode can discharge excess current from the regulator each cycle until the output voltage is less than the target voltage.

主权项

1. A switching mode power supply (SMPS), comprising:
a) a buck power regulator; b) an active diode capable of continuously varying a threshold voltage; c) a combining circuit capable of controlling the threshold voltage of the active diode, wherein a target input voltage is capable of being combined with an output voltage of the buck power regulator; and d) said buck power regulator capable of discharging a portion of excess current to circuit ground when an overvoltage resulting from a high output voltage causes the threshold voltage to rise to allow discharge of said portion of the excess current.