Patent ID: 8835974

Claim:
A driving device that drives a light emitting thyristor array including plural stages of light emitting thyristors, the plural stages of light emitting thyristors each including a first terminal, a second terminal, and a first control terminal that controls on and off switching between the first and second terminals, the first terminal being commonly connected to a first power source and the second terminal being commonly connected to a common terminal, the driving device comprising: a first driving circuit that is operated by a second power source and that drives the common terminal at high and low logic levels; a scanning circuit that includes plural stages of scanning thyristors and that sequentially scans the plural stages of light emitting thyristors, the plural stages of scanning thyristors each including a third terminal, a fourth terminal, and a second control terminal that controls on and off switching between the third and fourth terminals, the third terminal being commonly connected to the first power source, the second control terminal of each stage being connected to the first control terminal of a light emitting thyristor of a corresponding stage; and a second driving circuit that is operated by the second power source, that generates first and second clock signals for driving the scanning circuit, and that outputs the first and second clock signals from first and second clock terminals, respectively, wherein the fourth terminal of an odd numbered stage scanning thyristor is commonly connected to the first clock terminal, the fourth terminal of an even numbered stage scanning thyristor is commonly connected to the second clock terminal, and the second control terminal of a first stage scanning thyristor is connected to the second clock terminal via a first resistor.