Driving circuit with self-test function and test method thereof

Abstract

The invention discloses a driving circuit with a self-test function and a test method thereof. The data input circuit is coupled with a data line and a test voltage input end, the capacitor is coupled between the data input circuit and a control end of the power switch, a first end and a second end of the power switch are respectively coupled with a first operation voltage input end and the transmitting switch, and the compensation circuit is coupled between the control end and the second end of the power switch. The first switch is coupled between the compensation circuit and the data line, the emission switch is coupled between the second end of the power switch and the first pixel contact, the second pixel contact is coupled with the second operation voltage input end, and the first pixel contact and the second pixel contact are suitable for being coupled with display pixels. And controlling the conduction states of the data input circuit, the compensation circuit, the first switch and the emission switch. A test result signal is received from the data line.

Description

Technical Field

[0001] The present invention relates to a driving device, and particularly to a driving circuit with a self-test function and a testing method thereof. Background Art

[0002] The detection of a general pixel driving circuit is performed by measuring the magnitude of the current on a data line. In order to detect whether a specific component is abnormal, for example, whether a transistor can be normally turned on or off, additional circuit elements need to be provided in the pixel driving circuit for detection. For example, a transistor element coupled to the anode of a light-emitting diode is additionally provided to detect whether the power transistor driving the light-emitting diode can operate normally. However, as the pixel density of the display device becomes higher and higher, the circuit layout area of the pixel driving circuit is limited, and the method of setting additional circuit elements in the pixel driving circuit for detection is no longer applicable to the detection of the pixel driving circuit of a high pixel density display device. Summary of the Invention

[0003] The present invention provides a driving circuit with a self-test function and a testing method thereof, which can detect the driving circuit without additional circuit elements in the pixel driving circuit.

[0004] The driving circuit with a self-test function of the present invention includes a data input circuit, a capacitor, a power switch, a compensation circuit, a first switch, a transmitting switch, a first pixel contact, a second pixel contact, and a control circuit. The data input circuit is coupled to a data line and a test voltage input terminal. The first end of the capacitor is coupled to the data input circuit. The control end of the power switch is coupled to the second end of the capacitor, and the first end of the power switch is coupled to a first operating voltage input terminal. The compensation circuit is coupled between the control end and the second end of the power switch. The first switch is coupled between the compensation circuit and the data line. The transmitting switch is coupled between the second end of the power switch and the first pixel contact. The second pixel contact is coupled to a second operating voltage input terminal, and the first pixel contact and the second pixel contact are adapted to be coupled to a display pixel. The control circuit is coupled to the data line, the compensation circuit, the test voltage input terminal, the first operating voltage input terminal, the second operating voltage input terminal, the control end of the first switch, and the control end of the transmitting switch, controls the conduction states of the data input circuit, the compensation circuit, the first switch, and the transmitting switch, respectively provides a first operating voltage, a second operating voltage, and a test voltage to the first operating voltage input terminal, the second operating voltage input terminal, and the test voltage input terminal, receives a test result signal from the data line, and determines whether the driving circuit is abnormal according to the test result signal.

[0005] The present invention also provides a test method for a driving circuit with a self - test function. The driving circuit includes a data input circuit, a capacitor, a power switch, a compensation circuit, a first switch, a transmitting switch, a first pixel contact, and a second pixel contact. The data input circuit is coupled to a data line and a test voltage input terminal. The capacitor is coupled between the data input circuit and the control terminal of the power switch. The first end and the second end of the power switch are respectively coupled to a first operating voltage input terminal and the transmitting switch. The compensation circuit is coupled between the control terminal and the second end of the power switch. The first switch is coupled between the compensation circuit and the data line. The transmitting switch is coupled between the second end of the power switch and the first pixel contact. The second pixel contact is coupled to a second operating voltage input terminal. The first pixel contact and the second pixel contact are adapted to be coupled to a display pixel. The test method includes the following steps. Control the conduction states of the data input circuit, the compensation circuit, the first switch, and the transmitting switch, and respectively provide a first operating voltage, a second operating voltage, and a test voltage to the first operating voltage input terminal, the second operating voltage input terminal, and the test voltage input terminal. Receive a test result signal from the data line. Determine whether the driving circuit is abnormal based on the test result signal.

[0006] Based on the above, the driving circuit according to an embodiment of the present invention includes a data input circuit, a capacitor, a power switch, a compensation circuit, a first switch, a transmitting switch, and a second pixel contact. The data input circuit is coupled to a data line and a test voltage input terminal. The capacitor is coupled between the data input circuit and the control terminal of the power switch. The first end and the second end of the power switch are respectively coupled to a first operating voltage input terminal and the transmitting switch. The compensation circuit is coupled between the control terminal and the second end of the power switch. The first switch is coupled between the compensation circuit and the data line. The transmitting switch is coupled between the second end of the power switch and the first pixel contact. The second pixel contact is coupled to a second operating voltage input terminal. The first pixel contact and the second pixel contact are adapted to be coupled to a display pixel. By controlling the conduction states of the data input circuit, the compensation circuit, the first switch, and the transmitting switch, and receiving a test result signal from the data line, the driving circuit can be detected without additional circuit elements in the pixel driving circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figures 1 to 5 A schematic diagram showing the driving circuit according to an embodiment of the present invention is shown.

[0008] Figures 6 to 10 A flowchart showing the test method of the driving circuit according to an embodiment of the present invention is shown.

[0009] DESCRIPTION OF THE REFERENCE NUMERALS:

[0010] 100: Driving circuit

[0011] 102: Compensation circuit

[0012] 104: Data input circuit

[0013] 106: Control circuit

[0014] L1: Display pixel

[0015] T1: First switch

[0016] T2: Second switch

[0017] T3: Third switch

[0018] T4: Fourth switch

[0019] T5: Fifth switch

[0020] T6: Power switch

[0021] T7: Transmit switch

[0022] C1: Capacitor

[0023] P1: First pixel contact

[0024] P2: Second pixel contact

[0025] DL1: Data line

[0026] DC1: Test voltage

[0027] VDD: First operating voltage

[0028] VSS: Second operating voltage

[0029] S1, S2: Switch control signals

[0030] EM1: Transmit control signal

[0031] S602~S606, S702~S704, S802~S804, S902~S904, S1002~S1004: Test method steps Detailed implementation manners

[0032] Please refer to Figure 1 , Figure 1Schematic diagram of a driving circuit showing an embodiment of the present invention. The driving circuit 100 is used to drive the display pixel L1 to display an image screen. The driving circuit 100 may include a first switch T1, a power switch T6, a transmitting switch T7, a capacitor C1, a compensation circuit 102, a data input circuit 104, a control circuit 106, a first pixel contact P1, and a second pixel contact P2. The data input circuit 104 is coupled to the data line DL1 and a test voltage input terminal for receiving a test voltage DC1. The capacitor C1 is coupled between the data input circuit 104 and the control terminal of the power switch T6. The first terminal of the power switch T6 is coupled to a first operating voltage input terminal for receiving an operating voltage VDD. The compensation circuit 102 is coupled between the control terminal and the second terminal of the power switch T6. The first switch T1 is coupled between the compensation circuit 102 and the data line DL1. The transmitting switch T7 is coupled between the second terminal of the power switch T6 and the first pixel contact P1. The second pixel contact P2 is coupled to a second operating voltage input terminal for receiving an operating voltage VSS. The first pixel contact P1 and the second pixel contact P2 are adapted to be coupled to the display pixel L1. The display pixel L1 may be, for example, a light-emitting diode, but is not limited thereto. In the case where the display pixel L1 is implemented as a light-emitting diode, the first pixel contact P1 is adapted to be coupled to the anode of the light-emitting diode, and the second pixel contact P2 is adapted to be coupled to the cathode of the light-emitting diode. In addition, the control circuit 106 is coupled to the compensation circuit 102, the data line DL1, the test voltage input terminal, the first operating voltage input terminal, the second operating voltage input terminal, the control terminal of the first switch T1, and the control terminal of the transmitting switch T7.

[0033] The test method for the driving circuit 100 to perform self-test can be as follows Figure 6 shown. The control circuit 106 can control the conduction states of the data input circuit 104, the compensation circuit 102, the first switch T1, and the transmitting switch T7, respectively providing the first operating voltage VDD, the second operating voltage VSS, and the test voltage DC1 to the first operating voltage input terminal, the second operating voltage input terminal, and the test voltage input terminal (step S602), and receiving a corresponding test result signal from the data line DL1 (step S604) to determine whether the driving circuit 100 is abnormal based on the test result signal (step S606).

[0034] Furthermore, the compensation circuit 102 can be as follows Figure 1As shown, it includes a second switch T2 and a third switch T3. The second switch T2 and the third switch T3 are connected in series between the data line DL1 and the test voltage input terminal. The control terminals of the second switch T2 and the third switch T3 are coupled to the control circuit 106. The first switch T1 is coupled between the common contact point of the second switch T2 and the third switch T3 and the data line DL1. In addition, the data input circuit 104 may include a fourth switch T4 and a fifth switch T5. The fourth switch T4 and the fifth switch T5 are connected in series between the control terminal and the second terminal of the power switch T6. The control terminals of the fourth switch T4 and the fifth switch T5 are coupled to the control circuit 106. The common contact point of the fourth switch T4 and the fifth switch T5 is coupled to one end of the capacitor C1. Among them, the above-mentioned first switch T1 to fifth switch T5, power switch T6, and emission switch T7 are implemented by P-type transistors, but this is not limited thereto. In other embodiments, the first switch T1 to fifth switch T5, power switch T6, and emission switch T7 may also be implemented by different circuit elements, such as N-type transistors. The control circuit 106 can control the on-off states of the first switch T1 to fifth switch T5 and the emission switch T7 by outputting switch control signals S1, S2, and emission control signal EM1 to perform circuit element detection of the drive circuit 100.

[0035] Specifically, as Figure 2 shown in Figure 7 In the first mode, the control circuit 106 can turn on the second switch T2 to fifth switch T5 and the emission switch T7, and turn off the first switch T1 (step S702) to receive the test result signal provided by the fourth switch T4 to the data line DL1 from the data line DL1, and determine whether the fourth switch T4 and the fifth switch T5 are abnormal according to the test result signal (step S704), for example, whether the fourth switch T4 and the fifth switch T5 are damaged and cannot be turned on. In this embodiment, the test voltage DC1 is set to a high voltage logic level, and a current flowing from the test voltage input terminal to the data line DL1 is generated, thereby providing the test result signal to the data line DL1. However, in other embodiments, the test voltage DC1 can also be set to a low voltage logic level to generate a current flowing from the test voltage input terminal to the data line DL1 to detect whether the fourth switch T4 and the fifth switch T5 are abnormal. In addition, the operating voltages VDD and VSS can be set to the same voltage, for example, both set to the ground voltage to reduce power consumption, but this is not limited thereto.

[0036] As Figure 3 shown in Figure 8As shown, in the second mode, the control circuit 106 can turn on the second switch T2 to the fourth switch T4 and turn off the first switch T1, the fifth switch T5, and the emission switch T7 (step S802) to generate a current flowing through the power switch T6, the second switch T2, the third switch T3, the capacitor C1, and the fourth switch T4. Then, it can receive the test result signal provided by the fourth switch T4 to the data line DL1 from the data line DL1 and determine whether the capacitor C1 is abnormal based on the test result signal (step S804). In addition, it can also detect whether the power switch T6, the second switch T2 to the fourth switch T4 are abnormal at the same time. In the second mode, the operating voltage VDD can be set to a high voltage logic level, for example, and the test voltage DC1 and the operating voltage VSS can be set to the ground voltage to reduce power consumption, but this is not limited thereto.

[0037] As Figure 4 shown Figure 9 in the third mode, the control circuit 106 turns on the first switch T1 to the fifth switch T5 and the emission switch T7 (step S902) and determines whether there is a short circuit between the first pixel contact P1 and the second pixel contact P2 based on whether it receives the test result signal provided by the first switch T1 to the data line DL1 (step S904). In addition, it can also detect whether the emission switch T7, the second switch T2, and the first switch T1 are abnormal at the same time. The third mode is used to detect whether there is a short circuit between the first pixel contact P1 and the second pixel contact P2 when the display pixel L1 (light emitting diode) has not been formed in the driving circuit 100. As Figure 4 shown, if there is a short circuit between the first pixel contact P1 and the second pixel contact P2, a current will flow through the second pixel contact P2, the first pixel contact P1, the emission switch T7, the second switch T2, and the first switch T1. Then, it can receive the test result signal provided by the first switch T1 to the data line DL1 from the data line DL1 and determine that there is a short circuit between the first pixel contact and the second pixel contact. In the third mode, the operating voltage VDD can be set to a low voltage logic level, for example, the operating voltage VSS can be set to a high voltage logic level, and the test voltage DC1 can be set to the ground voltage, for example. It should be noted that in other embodiments, the third mode can also be applied to the case where the display pixel L1 has been formed in the driving circuit 100, and it can detect whether the display pixel L1 is abnormal.

[0038] As Figure 5 shown Figure 10As shown, in the fourth mode, the control circuit 106 turns on the first switch T1 to the fourth switch T4 and turns off the fifth switch T5 and the emission switch T7 (step S1002), so as to generate a current flowing through the power switch T6, the second switch T2, and the first switch T1. Then, the test result signal provided by the first switch T1 to the data line DL1 can be received from the data line DL1, and it is determined whether the power switch T6 is abnormal according to the test result signal (step S1004). In addition, it is also possible to detect whether the second switch T2 and the first switch T1 are abnormal at the same time. In the fourth mode, the operating voltage VDD can be set to, for example, a high voltage logic level, and the test voltage DC1 and the operating voltage VSS can be set to, for example, a ground voltage to reduce power consumption, but this is not limited thereto.

[0039] In summary, the driving circuit of the present invention includes a data input circuit, a capacitor, a power switch, a compensation circuit, a first switch, an emission switch, and a second pixel contact. The data input circuit is coupled to the data line and the test voltage input terminal. The capacitor is coupled between the data input circuit and the control terminal of the power switch. The first end and the second end of the power switch are respectively coupled to the first operating voltage input terminal and the emission switch. The compensation circuit is coupled between the control terminal and the second end of the power switch. The first switch is coupled between the compensation circuit and the data line. The emission switch is coupled between the second end of the power switch and the first pixel contact. The second pixel contact is coupled to the second operating voltage input terminal. The first pixel contact and the second pixel contact are adapted to be coupled to the display pixel. By controlling the conduction states of the data input circuit, the compensation circuit, the first switch, and the emission switch, and receiving the test result signal from the data line, the driving circuit can be detected without additional circuit elements in the pixel driving circuit.

Claims

1. A driving circuit with a self-test function, comprising: A data input circuit coupled to a data line and a test voltage input terminal; a capacitor, a first end of which is coupled to the data input circuit; a power switch, a control terminal of which is coupled to the second terminal of the capacitor, and a first terminal of the power switch is coupled to a first operating voltage input terminal; a compensation circuit coupled between the control terminal and the second terminal of the power switch; a first switch coupled between the compensation circuit and the data line; a first pixel contact; an emission switch coupled between the second end of the power switch and the first pixel contact; A second pixel contact, coupled to a second operating voltage input terminal, the first pixel contact and the second pixel contact are suitable for coupling to a display pixel; as well as A control circuit is coupled to the data line, the compensation circuit, the test voltage input terminal, the first operating voltage input terminal, the second operating voltage input terminal, the control terminal of the first switch and the control terminal of the transmitting switch, controls the conduction state of the data input circuit, the compensation circuit, the first switch and the transmitting switch, provides a first operating voltage, a second operating voltage and a test voltage to the first operating voltage input terminal, the second operating voltage input terminal and the test voltage input terminal respectively, receives a test result signal from the data line, and determines whether the driving circuit is abnormal according to the test result signal.

2. The driving circuit with self-test function as claimed in claim 1, wherein the compensation circuit comprises: a second switch; as well as A third switch is connected in series with the second switch between the second end and the control end of the power switch. The first switch is coupled between a common node of the second switch and the third switch and the data line. The conduction states of the second switch and the third switch are controlled by the control circuit.

3. The driving circuit with self-test function as claimed in claim 2, wherein the data input circuit comprises: a fourth switch; as well as A fifth switch is connected in series with the fourth switch between the data line and the test voltage input terminal. A common contact of the fourth switch and the fifth switch is coupled to the first end of the capacitor. The conduction states of the fourth switch and the fifth switch are controlled by the control circuit.

4. The driving circuit with a self-test function as claimed in claim 3, wherein in a first mode, the control circuit turns on the second switch to the fifth switch and the transmitting switch, turns off the first switch, and determines whether the fourth switch and the fifth switch are abnormal based on the test result signal provided by the fourth switch to the data line.

5. The driving circuit with a self-test function as claimed in claim 3, wherein in a second mode, the control circuit turns on the second switch to the fourth switch, turns off the first switch, the fifth switch and the transmitting switch, and determines whether the capacitor is abnormal based on the test result signal provided by the fourth switch to the data line.

6. A driving circuit with a self-test function as described in claim 3, wherein in a third mode, the control circuit turns on the first switch to the fifth switch and the emission switch, and determines whether the first pixel contact and the second pixel contact are short-circuited based on whether the test result signal provided by the first switch to the data line is received.

7. The driving circuit with self-test function as claimed in claim 3, wherein in a fourth mode, the control circuit turns on the first switch to the fourth switch, turns off the fifth switch and the transmitting switch, and determines whether the power switch is abnormal based on the test result signal provided by the first switch to the data line. 8 . The driving circuit with self-test function as claimed in claim 1 , wherein the display pixel is a light emitting diode, and an anode and a cathode of the light emitting diode are respectively coupled to the first pixel contact and the second pixel contact.

9. A method for testing a driving circuit with a self-test function, wherein the driving circuit comprises a data input circuit, a capacitor, a power switch, a compensation circuit, a first switch, an emission switch, a first pixel contact and a second pixel contact, the data input circuit is coupled to a data line and a test voltage input terminal, the capacitor is coupled between the data input circuit and the control terminal of the power switch, the first terminal and the second terminal of the power switch are respectively coupled to a first operating voltage input terminal and the emission switch, the compensation circuit is coupled between the control terminal and the second terminal of the power switch, the first switch is coupled between the compensation circuit and the data line, the emission switch is coupled between the second terminal of the power switch and the first pixel contact, the second pixel contact is coupled to a second operating voltage input terminal, the first pixel contact and the second pixel contact are suitable for coupling a display pixel, and the testing method comprises: Controlling the conduction states of the data input circuit, the compensation circuit, the first switch and the transmitting switch, and providing a first operating voltage, a second operating voltage and a test voltage to the first operating voltage input terminal, the second operating voltage input terminal and the test voltage input terminal respectively; receiving a test result signal from the data line; as well as Whether the driving circuit is abnormal is determined according to the test result signal.

10. The test method as described in claim 9, wherein the compensation circuit includes a second switch and a third switch, the third switch and the second switch are connected in series between the second end and the control end of the power switch, the first switch is coupled between the common contact of the second switch and the third switch and the data line, the conduction state of the second switch and the third switch is controlled by the control circuit, the data input circuit includes a fourth switch; and a fifth switch, the fifth switch and the fourth switch are connected in series between the data line and the test voltage input end, the common contact of the fourth switch and the fifth switch is coupled to the first end of the capacitor, and the conduction state of the fourth switch and the fifth switch is controlled by the control circuit.

11. The testing method according to claim 10, comprising: In a first mode, the second switch to the fifth switch and the transmitting switch are turned on, and the first switch is turned off; as well as Whether the fourth switch and the fifth switch are abnormal is determined according to the test result signal provided by the fourth switch to the data line.

12. The testing method according to claim 10, comprising: In a second mode, the second switch to the fourth switch are turned on, and the first switch, the fifth switch and the transmitting switch are turned off; as well as Whether the capacitor is abnormal is determined according to the test result signal provided by the fourth switch to the data line.

13. The testing method according to claim 10, comprising: In a third mode, turning on the first switch to the fifth switch and the emission switch; as well as Whether the first pixel contact and the second pixel contact are short-circuited is determined according to whether the test result signal provided by the first switch to the data line is received.

14. The testing method according to claim 10, comprising: In a fourth mode, the first switch to the fourth switch are turned on, and the fifth switch and the transmitting switch are turned off; as well as Whether the power switch is abnormal is determined according to the test result signal provided by the first switch to the data line. 15 . The testing method as claimed in claim 9 , wherein the display pixel is a light emitting diode, and an anode and a cathode of the light emitting diode are respectively coupled to the first pixel contact and the second pixel contact.

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