Method and circuitry for controlling start-up characteristics of a magnetic amplifier control circuit

摘要

Start-up control circuit (152) regulates the output voltage (VOS) of a power supply circuit (150). Magnetic amplifier control circuit (54) includes magnetic amplifier (42) and error detection circuitry (58, 68, and 70). Start-up control circuit (152) includes sensing circuitry (76 and 184) for generating sensing signals in response to voltage levels (VCC and VEE) in error detection circuitry (58, 68, and 70). Sensing signals indicate whether error detection circuitry (58, 68, and 70) voltage levels are sufficient to drive magnetic amplifier control circuit (54). Reset circuitry (190 and 192, and 194) associates with the sensing circuitry (76 and 184) for initially resetting magnetic amplifier (42) to prohibit output voltage (VOS) from power supply circuit (150) when the sensing signals indicate that voltage levels are insufficient for error detection circuitry to drive magnetic amplifier control circuit (54). Reset circuitry (190 192, and 194) further associates with reset control transistor (76) for controllably decreasing the reset of magnetic amplifier (42). Reset circuitry (190, 192, and 194) further associates with magnetic amplifier control circuit (54) for shifting control of magnetic amplifier (42) to magnetic amplifier control circuit (54) as voltage levels increase sufficiently for the error detection circuitry (58, 68, 70) to drive magnetic amplifier control circuit (54).