Title:
CONTROLLING CIRCUIT FOR POWER SUPPLY DEVICE
Document Type and Number:
Japanese Patent JPS5694963
Kind Code:
A
Abstract:
PURPOSE:To prevent the overcurrent flowing to the load and the main switching transistor by a method wherein an auxiliary control loop is provided in addition to the main control loop. CONSTITUTION:When the output level of a detector 3 came up to the reference voltage Vref1 and the amplifier 11 of the main control loop is in operation, an amplifier 12 is in ''OFF'' position and is statically controlled, because the reference voltage Vref2 of the auxiliary control loop is set at a high level. On the other hand, at the time of transient state, when the detecting output becomes larger than the reference voltage Vref2 during the period D of the response delay of the main control loop, the amplifier 12 of the auxiliary control loop, performing low-gain high-speed response, is operated and stabilized. Then, when the main control loop begins to response, the auxiliary control loop is placed in ''OFF'' condition again. Thus, the overcurrent arising from a short-circuit load and the like is controlled and the main switching transistor can be protected.
Inventors:
SATOU MITSUTAKE
KOUNO MICHIO
SAITOU YOSHIKATSU
KOUNO MICHIO
SAITOU YOSHIKATSU
Application Number:
JP16915479A
Publication Date:
July 31, 1981
Filing Date:
December 27, 1979
Export Citation:
Assignee:
FUJITSU LTD
International Classes:
H02M3/28; H02M3/335; (IPC1-7): H02M3/24