| 摘要 |
PURPOSE:To obtain a DC clamp circuit with simple constitution suitable for circuit integration by using a depletion Schottky barrier field effect transistor (TR) so as to form a DC negative feedback amplifier circuit. CONSTITUTION:A Schottky barrier diode between the gate and source of a depletion Schottky barrier field effect TR FET 2 is used as a clamp diode and the source of the FET 2 corresponding to the cathode of the diode is connected to a power supply -VF. ¦VF¦ is a forward voltage of the diode. A potential zero V of the input point A when the Schottky diode is cut off, is held by the voltage division of a resistive element R1 and a diode reverse resistance Rb. In this case, the ideal clamping is attained and excellent clamping is applied even to a signal of a small amplitude. Moreover, since the circuit 114 is formed as a common source negative feedback DC amplifier circuit, a wide band voltage gain is obtained. |
