Fig. 1. Diagram of OLED microdisplay system

Fig. 2. Simulation results of pixel circuits with different V_com

Fig. 3. Diagram of V_com PWM sequence

Fig. 4. Diagram of V_com PWM circuit architecture

Fig. 5. Circuit of negative voltage level-shift

Fig. 6. Simulation results of voltage at each node of level-shift circuit

Fig. 7. Rising and falling time simulation results of gate voltage for PMOS and NMOS

Fig. 8. Simulation results of pixel current under different V_com duty cycle

Fig. 9. V_com PWM layout

Fig. 10. Gray-scale characteristics of OLEDoS with different brightness adjusting modes