| 摘要 |
<p>PURPOSE:To facilitate the circuit integration and to easily obtain a required delay by connecting a variable current source onto a common current path of a,reproduction amplifier and controlling the variable current source so as to control the delay time of an output signal. CONSTITUTION:An equivalent load resistor having the same dynamic characteristic as that of an emitter resistor of transistors(TRs) Qa, Qb being components of a reproduction amplifier 2 employing a differential amplifier and whose resistance is larger than the resistance of the emitter resistor is connected to collectors of the TRs Qa, Qb. The equivalent load resistor is realized by diodes Da, Db and Dc, Dd. The equivalent load resistor is inversely proportional to a current flowing to the collector of the TRs Qa, Qb, and then a current flowing to a common path of the emitter side. The delay time in the output signal is controlled by the current. Thus, the delay time is controlled by varying a current source 15. Through the constitution above, since a desired delay is obtained without use of a variable capacitor or the like, the configuration is simplified and suitable for circuit integration.</p> |
