| 摘要 |
PURPOSE:To avoid the effect of a limit current due to temperature by constituting an output transistor(TR) with 1st and 2nd TRs and connecting a current mirror circuit to the collectors of the 1st and 2nd TRs. CONSTITUTION:A TR Q3 and a TR Q4 having an emitter area being a multiple of N of the emitter area of the TR Q3 are used as output TRs, a current sensing resistor R3 connects to the emitter of the TR Q4 and a current mirror circuit comprising TRs Q5, Q6 connects to the collector. Then a. Tr Q7 controlled by a collector level of the TR Q6 of the current mirror circuit is provided, a current flows to a resistor R4 by the conduction of the TR Q7 to control the TR Q2 for the current limit use. Thus, the effect of the limited current due to temperature is avoided and a current limit with a desired value is applied even when the temperature changes. |
