| 摘要 |
PURPOSE:To allow an output circuit to operate stably without causing an overcurrent to flow even when a source voltage rises by controlling the base currents of a 1st transistor(TR) which is supplied at its base with a current corresponding to an output voltage and a 2nd TR which is applied at its base with an output current. CONSTITUTION:An emitter back element is interposed between the base of a TR Q6 and a ground line 13, the emitter of an NPN type TR Q7 is connected to the base of the TR Q6, and the collector and base of the TR Q7 are connected to the ground line 13. A current which flows owing to the breakdown of the TR Q7 is limited with a current I4 flowing to a TR Q4 constituting a current mirror circuit, so no overcurrent flows. Thus, the circuit operation is prevented from becoming unstable owing to the breakdown of a TR Q3 and the circuit is prevented from breaking down. |
