| 摘要 |
PURPOSE:To obtain a high degree of gain through a simple cicuit constitution, by connecting in common both the collector of one of the two transistors of the adjacent comparators and the collector of the other transistor to a load means. CONSTITUTION:When an analog voltage signal VIN has a relation of VIN<V1 (V1-V3: reference voltage), transistors TRQ220, Q222, Q224and Q226 are turned off with TRQ221, Q223, Q226 and Q227 turned on respectively. As a result, only an amplifyng TRQ228 is turned on with only an output OUT1 set at a low level. In the case of V1<VIN<V2, the TRQ221 and Q222 are turned off to obtain a high level at the collector connected in common to TRQ221 and Q222. Thus only an output OUT2 obtained via an amplifying TRQ229 is set at a low level. After this, only an output OUT3 is set at a low level in the case of V2<VIN<V3. In such way, the gain of a high degree equivalent to that obtained through a 2-tier defferential amplifying circuit can be obtained. Furthermore the number of TRs and resistances are decreased significantly, and at the same time the power consumption can be reduced. |
