PURPOSE: To simplify circuit constitution and to facilitate IC-implementation by constituting the 1st and 2nd differential amplifying circuits by the combination of transistors (TR), and obtaining an output from the connection position between their collectors and bases.
CONSTITUTION: Transistors (TR) Q1 and Q2 constitute the 1st differential amplifying circuit 1, and TRs Q3 and Q4 constitute the 2nd differential amplifying circuit 2. Collectors of the TRs Q2 and Q3 are connected in common to a constant current loading circuit and also connected to their bases. Therefore, 100% of output signals of the differential amplifying circuits 1 and 2 is fed back negatively. On the other hand, an output signal Vout is obtained from the connection position between their collectors and bases. Emitters of the TRs Q1 and Q2 are connected to a power source Vcc through a TRQ5 and a resistance R1, and emitters of the TRs Q3 and Q4 are connected to the power source Vcc through a TRQ6 and a resistance R2. The 1st input signal Vin1 is applied to the base of the TRQ1, and the 2nd input signal Vin2 is applied to the base of the TRQ4 to putting either of the TRs Q5 and Q6 in operation selectively, thus obtaining an output signal Vout which responds to either of the Vin1 and Vin2.
WATANABE KAZUO
NAMIENO AKIRA
SASAKI MASARU
PIONEER ELECTRONIC CORP
| JPS53138265A | 1978-12-02 | |||
| JPS5236813A | 1977-03-22 |