| 摘要 |
PURPOSE:To set up a clamp level optionally and to take out signals at a low distortion ratio until a moment just before the clamp level by performing upper and lower clamping by using a differential transistor (TR) circuit. CONSTITUTION:In the basic constitution of a clamping circuit, voltage corresponding to the clamp level is applied to one base of the differential TR circuit and an input signal is applied to the other base. Therefore, the clamp level is determined by the base voltage of the TRs 13, 15. Lower clamping is performed by making current flow into the TRs 11, 13. On the other hand, upper clamping is performed by making current flow into TRs 12, 14. The clamp level can be changed by the size of resistors 16, 17 and constant power supplies 21, 22. |
