Patent ID: 7816955
Filing Date: 2010-10-19
Classification: H01J,H03K

Abstract:
1. A ramp generator comprising: a capacitor for charging/discharging current; a charge current source for charging the capacitor; a discharge current source for discharging the capacitor; a first feedback circuit; a first selector; a second feedback circuit; and a second selector, wherein the first feedback circuit is connected to the first selector and the capacitor, the second feedback circuit is connected to the second selector and the capacitor, the first selector selects whether the discharge current source is connected to the capacitor via the first feedback circuit, the discharge current source is directly connected to the capacitor, or the discharge current source is opened, the second selector selects whether the charge current source is connected to the capacitor via the first feedback circuit, the charge current source is directly connected to the capacitor, or the charge current source is opened, charging of the capacitor starts when the first selector opens the discharge current source, discharging of the capacitor starts when the second selector opens the charge current source, and a ramp waveform is outputted from a connection point of the capacitor, the first feedback circuit, the second feedback circuit, the first selector and the second selector.