| 摘要 |
PROBLEM TO BE SOLVED: To secure a high ON/OFF threshold voltage (Vth) and to enable stable ON/OFF control by setting the threshold voltage of drive/stop at the base/ emitter voltage of a transistor to be leveled not to generate any malfunction caused by noise. SOLUTION: The threshold voltage of an ON/OFF circuit 3 is set at the base/emitter voltage of a transistor Tr24 so as to be leveled not to generate any malfunction caused by noise, and the temperature characteristics of an amplifier A2 are set so that a clamp voltage (VCL) at the output part of the amplifier A2 to an external control terminal Vc can be always higher than the threshold voltage of the ON/OFF circuit 3. Since the condition of VCL>Vth is established over the entire range of bonding temperature, the malfunction that the ON/OFF circuit 3 turns off a power source at the time of input voltage ON because of the input voltage or load state of the power source is not generated and a high-reliability stabilized power source circuit can be provided. |
