A circuit structure for studying the use of overdrive technology in pixel units of a resistor array is designed. Compared with the implementation methods of overdrive technologies of foreign countries, this method adopts an open-loop control form. It can remove the steps of closed-loop calculation and table look-up, save system resources and improve the real-time performance of the system. The circuit structure is designed after analyzing the principle of the overdrive technology. It can meet the requirements for studying the thermal response time t1, overdrive factor Kod and dynamic range of temperature of a micro-bridge of the resistor array. In addition, it conforms to the area constraint of a pixel unit. Its Kod is tunable in the range from 1 to 1.5. After simulation and layout design are carried out, the circuit is manufactured in the 0.5 μm process by CSMC foundry. Finally, the function of the circuit is verified by a special test system established. The result shows that the factor Kod of the circuit meets the design requirement.