AMOLED driving circuit, AMOLED driving method, and AMOLED display device

摘要

In embodiments of the present disclosure, there are provided an AMOLED driving circuit, an AMOLED driving method and an AMOLED display device. The AMOLED driving circuit includes a light emitting device, a first switching transistor, a voltage regulator, a driving transistor and a capacitor. The driving transistor in the AMOLED driving circuit drives the light emitting device to emit light under the control of the voltage regulator, a driving current provided by the driving transistor is independent of Vth of the driving transistor, so that the driving current flowing through the light emitting device is prevented from being affected by the poor uniformity and drift of Vth, the uniformity in the driving currents flowing through the light emitting devices is enhanced, and thus the uniformity in the brightness of the AMOLED is improved.

主权项

1. An AMOLED driving circuit, comprising:
a light emitting device, a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a fifth switching transistor, a voltage regulator, a driving transistor and a capacitor, the first switching transistor, the second switching transistor, the third switching transistor, the fourth switching transistor, the fifth switching transistor and the driving transistor are all N-type thin film transistors, wherein, a gate of the first switching transistor is connected with a first control line, a first electrode of the first switching transistor is connected with a data line, and a second electrode of the first switching transistor is connected with a first terminal of the capacitor; a gate of the second switching transistor is connected with a second control line, a first electrode of the second switching transistor is connected with the first terminal of the capacitor, a second electrode of the second switching transistor is connected with and a gate of the driving transistor; a gate of the third switching transistor is connected with the first control line, a first electrode of the third switching transistor is connected with the gate of the driving transistor, a second electrode of the third switching transistor is connected with a second electrode of the driving transistor and negative electrode of the light emitting device; a gate of the fifth switching transistor is connected with the second control line, a first electrode of the fifth switching transistor is connected with a reference voltage power supply, and a second electrode of the fifth switching transistor is connected with a first electrode of the driving transistor; the first electrode of the driving transistor is connected with a second terminal of the capacitor, and the second electrode of the driving transistor is connected with the negative electrode of the light emitting device; a gate of the fourth switching transistor is connected with the first control line, a first electrode of the fourth switching transistor is connected with a positive electrode of the light emitting device, and a second electrode is connected with the negative electrode of the light emitting device, the positive electrode of the light emitting device is connected with a high voltage power supply, and a level of the high voltage power supply is higher than a level of the reference voltage power supply, wherein in a first stage, the first control line is at an active level, the first switching transistor, the third switching transistor and the fourth switching transistor are turned on so that the data line provides a voltage to the capacitor; the second control line is at an inactive level, the second switching transistor and the fifth switching transistor are turned off, such that the first electrode of the capacitor is charged to a voltage at the data line and the second electrode of the capacitor is charged to a voltage equal to the voltage at the high voltage power supply minus a threshold voltage of the driving transistor, wherein the threshold voltage of the driving transistor is bigger than 0; in a second stage, the first control line is at an inactive level, the first switching transistor, the third switching transistor and the fourth switching transistor are turned off; the second control line is at an inactive level, the second switching transistor and the fifth switching transistor are turned off so that the capacitor remains the voltage; and in a third stage, the first control line is at an inactive level, the first switching transistor, the third switching transistor and the fourth switching transistor are turned off; the second control line is at an active level, the second switching transistor and the fifth switching transistor are turned on so that the driving transistor drives the light emitting device to emit light.