| 摘要 |
PURPOSE:To make a circuit simple and usable for multiple-purpose by providing the first and the second current paths, which are operated to the conduction or non-conduction state in accordance with variance of the level of a control signal to obtain a desired voltage level, to change an output level. CONSTITUTION:When a control signal VC is in the low level, transistors (TRs) Q1 and Q4 are turned off, and TRs Q2 and Q3 are turned on. Consequently, the voltage of a one-end terminal is clamped at V1 by TRs Q2 and Q3. A resistance R2 is set to a large value. Then, the voltage equal to the reference voltage V1 appears in the one-end terminal when the signal VC is in the low level. When the signal VC is in the high level, TRs Q1 and Q4 are turned on, and TRs Q2 and Q3 are turned off. Consequently, the voltage of an input signal Vin of the one-end terminal is clamped at V2 by TRs Q1 and Q4. A resistance R1 is set to a large value. Then, the voltage equal to the reference voltage V2 appears in the one-end terminal when the signal VC is in the high level. |
