| 摘要 |
PURPOSE:To form a saw-tooth wave of a high accuracy by delaying a synchronizing signal by using a delaying circuit set to a delay time which is equivalent to a delay time in a voltage comparing circuit, and compensating an inclination of the saw-tooth wave to the delay time. CONSTITUTION:When a synchronizing signal RS becomes a low level, a reset state of a charging and discharging circuit SW is released, and a charge to a capacitor is started by a constant-current, therefore, its voltage rises linearly in accordance with its time constant, and when it reaches voltage VP+VOS, an output signal A of a voltage comparing circuit VC is varied to a low level by being delayed by its operating delay time. On the other hand, when the synchronizing signal RS is varied to a high level from a low level, a reset state of a charging and discharging circuit SAW' is released and a charging operation is executed, and an output signal B is varied to a high level by being delayed by a delay time td'. A phase compensation of both input signals in the input side of a phase comparing circuit can be executed by making a delay time td and td' equal to each other. |
