| 摘要 |
PURPOSE:To improve reliability and safety by switching an overvoltage corresponding to an output voltage and performing short-circuit control over an output. CONSTITUTION:A reference voltage 16 is compared 12 with the detection output of an output voltage setting circuit 14 and a transistor (TR) 4 is controlled through a driving circuit 10 by the error output to obtain a stabilized output. This is supplied from output terminals 8A and 8B to a load through a smoothing circuit 6. Further, a triac 44 is connected to the output terminals and short-circuit protection is peformed in an overvoltage state with a signal from an overvoltage setting circuit 34. In this case, voltage division ratios of a switching circuit 24 are changed with a switch 32 to alter the setting circuit 14, but this voltage is applied to the overvoltage setting circuit 34 to turn on and off a TR26, and the set voltage of the overvoltage is switched to perform overvoltage protec- tion corresponding to the output voltage. |
