| 摘要 |
PURPOSE:To keep an output level constant over a wide range, by canceling the temperature fluctuation of an output level caused by the temperature fluctuation of a base-emitter voltage of an output transistor (TR) in a current switching circuit such as a binary logical circuit. CONSTITUTION:A temperature compensating circuit 31 where the temperature coefficient of a base potential of output TRs 45, 46 is negative, is connected to the base of the output TRs 45, 46, and an output level is compensated in terms of temperature over a wide range. That is, when input terminals 41, 42 are both at a low potential, a switching current flows to a resistor 48 and TRs 50 and 47, and also to a resistor 48, a diode 33, and a resistor 35, or a resistor 49, a diode 32 and a resistor 34, because both ends of diodes 32, 33 have a sufficient potential difference as the forward bias. Thus, the temperature coefficient of the base potential of the output TR can be set as an optional negative value, and the output voltage being a high or a low potential state is kept almost constant over a wide range without being effected with the ambient temperature. |
