Patent ID: 6937219

Claim:
An pixel circuit for active matrix of current driving devices, comprising: a first transistor, the source and the gate of said first transistor being separately electrically coupled with a first terminal and a second terminal; a second transistor, the source and the gate of said second transistor being separately electrically coupled with the drain of said first transistor and a third terminal; a third transistor, the source and drain of said third transistor being separately electrically coupled with a constant voltage source and the drain of said first transistor; a fourth transistor, the source and the gate of said fourth transistor being separately electrically coupled with said constant voltage source and the gate of said third transistor; an auxiliary transistor, the source, the drain and the gate of said auxiliary transistor being separately electrically coupled with the drain of said second transistor, the gate of said third transistor, and a fourth terminal; a capacitor, one plate of said capacitor being electrically coupled with said constant voltage source and another plate of said capacitor being electrically coupled with the gate of said fourth transistor; and a current driving device, said current driving device being electrically coupled with the drain of said fourth transistor.