| 摘要 |
PURPOSE:To use a level converting circuit with a single power source and to simplify the circuit constitution by using at least one input terminal as a digital input terminal through a resistance and connecting the emitter of at least one transistor (TR) to said input terminal, and connecting the collector of said TR to the power source and connecting the collector of said TR to the power source and the base to a proper bias potential. CONSTITUTION:One of inputs of a differential current switch circuit 10 is connected to a reference voltage V0 and the other forms the digital input terminal B1 through the resistance 20. Bases of npn TR T1 and a pnp TR T2 are connected to reference voltages V1(V0+DELTAV1) and V2(V0-DELTAV2) respectively. Thus, the input voltage potential variation width of the differential circuit is suppressed relatively small to evade the saturation of a differential TR which is a principal factor of a decrease in switching speed, and consequently, a converting circuit is used with a single power source of +5V and the variation width of the output potential of the level converting circuit is suppressed, thereby realizing high-speed switching operation. |
