Source driver and display device with temperature sensor

Abstract

The present invention provides a source driver and a display device having a temperature sensor. The embodiment relates to a temperature sensor having a correction function and can reduce a measurement error of the temperature sensor by calibrating the correlation between temperature and voltage.

Description

Technical Field

[0001] The present embodiment relates to a temperature sensor having a correction function, and also to a source driver and a display device including the temperature sensor. Background Art

[0002] Temperature sensors detect ambient heat and are widely used in semiconductor integrated circuits. In particular, temperature sensors can detect the temperature of heat-sensitive components in display devices, and panel driving devices can appropriately control the voltage or current supplied to the components according to the detected temperature.

[0003] A temperature sensor can detect temperature using electrical characteristics that change with heat. A temperature sensor can output electrical characteristics such as current that change according to temperature, and can calculate temperature based on these electrical characteristics. However, there may be a difference between the actual temperature and the temperature output by the temperature sensor.

[0004] Various techniques have been developed to correct the above errors. To correct these errors, the temperature data can be corrected at the simulation stage, but this has the disadvantage of requiring complex circuits to perform the correction. In addition, if the temperature sensor calculates the temperature through the nonlinear characteristics of the voltage, a difference may occur between the calculated temperature and the actual temperature.

[0005] On the other hand, the temperature sensor may introduce errors due to several factors. For example, the ground voltage of the temperature sensor may fluctuate, so the voltage output by sensing of the temperature sensor may be different. Alternatively, if the source driver of the display device performs an operation that consumes a lot of power, the internal temperature becomes higher than its actual temperature, and the temperature sensor installed inside the source driver may sense a temperature different from the actual temperature.

[0006] Therefore, there is a need to develop a technology for calibrating a temperature sensor that can solve the existing error correction problems of the temperature sensor and take into account the heat generated due to power consumption. Summary of the invention

[0007] In this context, one aspect of the present embodiment is to provide a technique for correcting a measurement error of a temperature sensor by calibrating the correlation between temperature and voltage. Another aspect of the present embodiment is to provide a temperature correction technique that differs according to the power consumption of a source driver. Another aspect of the present embodiment is to provide a technique for a source driver that is used to measure the temperature of a panel using thermal conductivity.

[0008] To this end, one aspect of the present invention provides a source driver, comprising: a calibration circuit, which is configured to differently obtain multiple temperature data and multiple voltage data corresponding to the multiple temperature data according to various modes depending on the power consumption of the source driver, and generate a function between temperature and voltage based on the obtained multiple temperature data and the obtained multiple voltage data; and a data calculation circuit, which is configured to receive input voltage data and apply the input voltage data to the function, thereby calculating temperature data corresponding to the input voltage data.

[0009] In the source driver, the mode may include a first mode for a first power consumption and a second mode for a second power consumption lower than the first power consumption, and the source driver may also include a memory configured to store a first set of multiple temperature data and a first set of multiple voltage data according to the first mode, and a second set of multiple temperature data and a second set of multiple voltage data according to the second mode.

[0010] In the source driver, the calibration circuit may read out a plurality of temperature data and a plurality of voltage data from the memory according to the pattern, and generate the function according to the read plurality of temperature data and the read plurality of voltage data.

[0011] In the source driver, the power consumption may be determined by the refresh rate RR of the panel.

[0012] The source driver may further include a memory configured to store offset data, and the calibration circuit may generate the function according to data obtained by reflecting the offset data to the plurality of voltage data.

[0013] In the source driver, the calibration circuit may include a multiplexer (MUX) configured to select the plurality of voltage data or the offset data.

[0014] The source driver may further include a temperature sensor configured to generate a signal corresponding to the plurality of voltage data and the input voltage data.

[0015] Another aspect of the present invention provides a display device, comprising: a panel; and a source driver, coupled to a surface of the panel and configured to: receive heat from the panel, obtain first temperature data, first voltage data corresponding to the first temperature data, second temperature data and second voltage data corresponding to the second temperature data, generate a function between temperature and voltage based on the first temperature data, the first voltage data, the second temperature data and the second voltage data, receive third voltage data, and calculate third temperature data corresponding to the third voltage data by applying the third voltage data to the function.

[0016] The display device may further include a heat dissipation plate located between the panel and the source driver to transfer heat from the panel to the source driver.

[0017] In the display device, the third temperature data is the temperature of the panel.

[0018] Another aspect of the present invention provides a source driver, comprising: a calibration circuit configured to obtain first temperature data, first voltage data corresponding to the first temperature data, second temperature data, and second voltage data corresponding to the second temperature data, and generate a function between temperature and voltage based on the first temperature data, the first voltage data, the second temperature data, and the second voltage data; and a data calculation circuit configured to receive third voltage data, and calculate third temperature data corresponding to the third voltage data by applying the third voltage data to the function.

[0019] The source driver may further include a memory configured to store data, and the calibration circuit may read out the first temperature data, the first voltage data, the second temperature data, and the second voltage data from the memory.

[0020] The source driver may further include a temperature sensor configured to generate first to third analog signals corresponding to the first to third voltage data according to temperature.

[0021] The source driver may further include an analog-to-digital converter configured to digitize the first to third analog signals into the first to third voltage data.

[0022] In the source driver, the function may be a linear function obtained by combining the first temperature data, the first voltage data, the second temperature data, and the second voltage data.

[0023] In the source driver, the calibration circuit may generate the function by adjusting a slope of the function and an offset of the function.

[0024] As described above, the present invention enables reduction of the error of temperature sensing due to power consumption of the source driver. In addition, the present invention enables reduction of the error of the temperature of the panel measured by the source driver. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 shows the structure of a display device according to an embodiment;

[0026] Figure 2 is a diagram showing an example of a structure of a source driver according to an embodiment;

[0027] Figure 3 is a circuit diagram showing an example of a temperature sensor according to an embodiment;

[0028] Figure 4 is a diagram showing an example of the structure of a data processing circuit and a calibration circuit according to the embodiment;

[0029] Figure 5 is a diagram illustrating a process of processing data according to an embodiment;

[0030] Figure 6 is a diagram illustrating a process of generating a function according to an embodiment;

[0031] Figure 7 is a diagram showing a process of selecting data differently according to a display mode in a calibration circuit according to another embodiment;

[0032] Figure 8 is a diagram showing a process of selecting offset reflection data according to a display mode in a calibration circuit according to another embodiment;

[0033] Fig. 9 is a diagram showing a structure of a display device according to another embodiment;

[0034] Fig.10 is a cross-sectional view showing an example of coupling between a source driver and a panel according to another embodiment;

[0035] Fig.11 is a diagram showing a first example of experimental results for calibration of temperature according to an embodiment of the present invention;

[0036] Fig.12 is a diagram showing a second example of experimental results for calibration of temperature according to an embodiment of the present invention;

[0037] Fig.13is a diagram showing a third example of experimental results for calibration of temperature according to an embodiment of the present invention;

[0038] Fig.14 is a diagram showing a first example of a conventional temperature sensing error; and

[0039] Fig.15 2 is a diagram showing a second example of a conventional temperature sensing error. DETAILED DESCRIPTION

[0040] Figure 1 The structure of a display device according to the embodiment is shown.

[0041] refer to Figure 1 The display device 100 may include a panel 110, a source driver 120, a gate driver 130, a timing controller 140, and the like.

[0042] A plurality of data lines DL, a plurality of gate lines GL, and a plurality of sensing lines SL may be disposed on the panel 110 , and a plurality of pixels P may be disposed on the panel 110 .

[0043] The gate driver (GDIC) 130 may supply a scanning signal of a turn-on voltage or a turn-off voltage to the gate line GL. When the scanning signal of the turn-on voltage is supplied to the pixel P, the corresponding pixel P is connected to the data line DL, and when the scanning signal of the turn-off voltage is supplied to the pixel P, the corresponding pixel P is disconnected from the data line DL.

[0044] The source driver (SDIC) 120 supplies data voltages to the data lines DL. The data voltages supplied to the data lines DL are transmitted to the pixels P connected to the data lines DL according to the scan signals.

[0045] The source driver 120 senses characteristic values ​​(eg, voltage and current) in each pixel P. The source driver 120 may be connected to each pixel P according to a scan signal, or may be connected to each pixel P according to a separate sensing signal. At this time, the sensing signal may be generated by the gate driver 130 .

[0046] The timing controller (T-CON) 140 may supply various control signals to the gate driver 130 and the source driver 120. The timing controller 140 may generate a gate control signal GCS for initiating scanning according to the timing implemented in each frame, and may send the gate control signal GCS to the gate driver 130. In addition, the timing controller 140 may output the following image data RGB to the source driver 120, which is obtained by converting the image data input from the outside to conform to the data signal format used by the source driver 120. In addition, the timing controller 140 may send a data control signal DCS for controlling the source driver 120 to supply a data voltage to each pixel P according to each timing.

[0047] The timing controller 140 may compensate the image data RGB according to the characteristics of the pixel P, thereby transmitting the image data RGB. At this time, the timing controller 140 may receive the pixel sensing data SENSE_DATA from the source driver 120. The pixel sensing data SENSE_DATA may include a measured value of the characteristic of the pixel P. The pixel sensing data SENSE_DATA may include a measured value of the data voltage output by the source driver 120 to the data line DL. The pixel sensing data SENSE_DATA may include data related to the temperature of the panel. The timing controller 140 may identify the temperature of the panel according to the temperature data, and may control the power management IC (PMIC) according to the temperature of the panel to supply an appropriate voltage to the panel.

[0048] The panel 110 may be an organic light emitting display panel. In this case, the pixels P configured on the panel 110 may include an organic light emitting diode (OLED) and one or more transistors. The characteristics of the organic light emitting diode (OLED) and the transistor included in each pixel P may vary according to time or the surrounding environment, and the source driver 120 may sense the characteristics of the components included in each pixel P, thereby sending the characteristics to the timing controller 140.

[0049] Figure 2 is a diagram showing an example of a structure of a source driver according to an embodiment, and Figure 3 is a circuit diagram showing an example of a temperature sensor according to the embodiment.

[0050] refer to Figure 2 The source driver 120 may include a temperature sensor 121 , an analog-to-digital converter (ADC) 122 , a data processing circuit 123 , a calibration circuit 124 , a data calculation circuit 125 , and a data output circuit 126 .

[0051] The temperature sensor 121 may sense the temperature of the source driver 120. The temperature sensor 121 may be provided inside the source driver 120, and may detect the temperature of the source driver 120, thereby outputting a current or a voltage corresponding to the detected temperature.

[0052] refer to Figure 3 The temperature sensor 121 may include a transistor, for example, a proportional to absolute temperature (PTAT) circuit including a bipolar junction transistor (BJT). The circuit of the temperature sensor 121 may include a metal oxide semiconductor field effect transistor (MOSFET), an amplifier and a resistor, and the BJT. Due to the voltage difference between the BJT terminals that varies according to the temperature, the temperature sensor 121 may cause I PTAT or V PTAT That is, the temperature sensor 121 can generate an I corresponding to the ambient temperature. PTAT or V PTAT I PTAT or V PTAT Specifically, the temperature sensor 121 may express the temperature and I as shown in the following equation 1: PTAT or V PTAT The relationship between.

[0053] [Equation 1]

[0054]

[0055] Here, “k” may represent the Boltzmann constant, “q” may represent the charge, “T” may represent the temperature in degrees Kelvin, R2 and R3 may represent the resistance, and V BE1 may represent the voltage between the base and emitter of the first BJT Q1, and V BE2 It can represent the voltage between the base and emitter of the second BJT Q2. The "n" in ln(n) is a coefficient representing the size of the contact area A between the base and the emitter, and is a constant. Therefore, according to Equation 1, since V PTAT and T can be expressed as a linear function, so the temperature sensor 121 can output V proportional to T PTAT .

[0056] Return to reference Figure 2 , the temperature sensor 121 may output a sensing signal S_SENSE corresponding to the temperature. The sensing signal S_SENSE may include a voltage signal. The voltage signal may be related to V in Equation 1. PTAT The temperature sensor 121 may send a sensing signal S_SENSE to the analog-to-digital converter 122 .

[0057] The analog-to-digital converter 122 may digitally convert the sensing signal S_SENSE, thereby generating digital sensing data D_SENSE. The sensing signal S_SENSE may include an analog voltage value, and the digital sensing data D_SENSE may include a digital voltage value. The digital sensing data D_SENSE may be filtered by the data processing circuit 123 and then may be used to generate a function between temperature and voltage in the calibration circuit 124.

[0058] The data processing circuit 123 may process the digital sensing data D_SENSE. The data processing circuit 123 may remove noise from the digital sensing data D_SENSE and may output processed sensing data SENSE_OUT. The processed sensing data SENSE_OUT may include digitized voltage data. The data processing circuit 123 may send the processed sensing data SENSE_OUT to the calibration circuit 124 and the data calculation circuit 125.

[0059] The calibration circuit 124 may generate a correlation between temperature and voltage and may calibrate the correlation. The data calculation circuit 125 may calculate a new temperature, ie, a calibration temperature, based on the calibrated correlation. The correlation may include a function having variables of temperature and voltage.

[0060] For example, the calibration circuit 124 may generate a function between temperature and voltage based on the processed sensing data SENSE_OUT. The processed sensing data SENSE_OUT may include voltage data and may be stored in a memory device (not shown) together with the temperature data in a manner corresponding to the temperature data. The calibration circuit 124 may generate a function between temperature and voltage based on the temperature data stored in the memory device (not shown) and the voltage data included in the processed sensing data SENSE_OUT, and may send the function to the data calculation circuit 125.

[0061] The data calculation circuit 125 may calculate the calibration temperature data CAL_TEMP_OUT according to the function. The data calculation circuit 125 may receive the function data FUNCTION from the calibration circuit 124, and may receive the processed sensing data SENSE_OUT from the data processing circuit 123. The data calculation circuit 125 may calculate the calibration temperature data CAL_TEMP_OUT by applying the processed sensing data SENSE_OUT to the function included in the function data FUNCTION. Since the temperature sensor 121 is operated in a state of being included in the source driver 120, the calibration temperature data CAL_TEMP_OUT may be the temperature of the source driver 120. Alternatively, if the heat of the panel 110 is transferred to the source driver 120, the calibration temperature data CAL_TEMP_OUT may be the temperature of the panel 110.

[0062] The data output circuit 126 can output the calibration temperature data CAL_TEMP_OUT. Before outputting the data, the data output circuit 126 can adjust the setting of the bit of the calibration temperature data CAL_TEMP_OUT. The data output circuit 126 can output the set temperature data. For example, the data output circuit 126 can reduce the number of bits of the calibration temperature data CAL_TEMP_OUT. If the calibration temperature data CAL_TEMP_OUT includes a decimal point, the bits after the decimal point can be deleted. Optionally, a digital signature code can be configured for the calibration temperature data CAL_TEMP_OUT.

[0063] Figure 4 is a diagram showing an example of the structure of a data processing circuit and a calibration circuit according to an embodiment, Figure 5 is a diagram showing a process of processing data according to an embodiment, and Figure 6 is a diagram illustrating a process of generating a function according to an embodiment.

[0064] refer to Figure 4 , the data processing circuit 123 may include a filter 411 and an average value generating circuit 412. The data processing circuit 123 may remove noise from the digital sense data D_SENSE using the filter 411 and the average value generating circuit 412.

[0065] refer to Figure 5 , showing the process of removing noise using the filter 411 and the average value generating circuit 412.

[0066] First, filter 411 can obtain the temperature sensor ( Figure 2 The filter 411 can obtain the median value of the data sensed by the analog-to-digital converter ( Figure 2122) receives the digital sensing data D_SENSE. The filter 411 can sample the digital sensing data D_SENSE to a specific number and can calculate a median value based on the sampled data.

[0067] For example, the filter 411 may receive a series of digital sensing data D_SENSE in the order of 304, 295, 301, 298, 300, 300, ... Each digital sensing data D_SENSE may be sent as a 9-bit binary number. However, the present invention is not limited thereto, and the digital sensing data D_SENSE may be extended to more than 9 bits, or may be reduced to less than 9 bits, depending on its design. The filter 411 may extract a plurality of digital sensing data D_SENSE via a sampling window 510. The sampling window 510 may also sample in units of 9 bits according to the digital sensing data D_SENSE, and the unit may be extended or reduced. The sampling window 510 may extract basic data for calculating a median from a series of digital sensing data D_SENSE. In this example, the sampling window 510 may sample three consecutive digital sensing data D_SENSE 301, 298, and 300. The filter 411 may calculate a median 520 of the sampled digital sense data D_SENSE 301 , 298 , and 300 . In this example, the median may be 300 .

[0068] The filter 411 may initiate sampling at any point of the digital sensing data D_SENSE, and may perform sampling from the starting point or the middle point of the received digital sensing data D_SENSE. For example, the filter 411 may initiate sampling from 304 as the starting point of the digital sensing data D_SENSE, thereby sampling 304, 295, and 301, or may initiate sampling from 301 as the middle point of the digital sensing data D_SENSE, thereby sampling 301, 298, and 300.

[0069] The filter 411 may generate a plurality of median values. To generate a plurality of median values, the filter 411 may shift the sampling window 510 by a constant unit, thereby performing sampling, and may continue to generate a median value based on the sampled digital sensing data D_SENSE. For example, the filter 411 may sample 301, 298, and 300, and then may shift the sampling window 510 by one unit, thereby sampling 298, 300, and 300. The filter 411 may calculate the median value 300 based on 298, 300, and 300.

[0070] The average value generation circuit 412 may calculate an average value from a plurality of median values ​​generated from the digital sense data D_SENSE using the filter 411. The average value generation circuit 412 may calculate an average value of all or a portion of the plurality of median values. The average value generation circuit 412 may use a decimal point to generate an accurate average value. The average value generation circuit 412 may generate processed sense data SENSE_OUT including the average value.

[0071] For example, the average value generation circuit 412 may receive median data from the filter 411. The filter 411 may shift the sampling window 510 by one unit from 301, 298, and 300, thereby generating median data including 300, 300, 300, 300, 301, 301, 298, and 298. The average value generation circuit 412 may calculate 299.750 as the average value of 300, 300, 300, 300, 301, 301, 298, and 298. The average value generation circuit 412 may generate a total of 17 bits of processed sensing data SENSE_OUT including 9 bits representing "299" before the decimal point and 8 bits representing "750" after the decimal point. The value after the decimal point in the processed sensing data SENSE_OUT is not limited to 8 bits, and may be extended to more than 8 bits or reduced to less than 8 bits according to its design.

[0072] Return to reference Figure 4 , the calibration circuit 124 may include a memory 421 and a function generation circuit 422. The processed sensing data SENSE_OUT may be stored in the memory 421 together with the temperature data in a manner corresponding to the temperature data. The function generation circuit 422 may generate a function between temperature and voltage according to the stored voltage data of the processed sensing data SENSE_OUT and the temperature data corresponding to the voltage data.

[0073] The calibration circuit 124 may receive the processed sensing data SENSE_OUT including the average value and store the processed sensing data SENSE_OUT in the memory 421. Specifically, the temperature sensor 121 may sense the ambient temperature and may output V according to the sensed temperature. PTAT and can be based on the output V PTAT The voltage data is generated. The processed sensing data SENSE_OUT including the voltage data may be stored in the memory 421 in a state of matching with the temperature data corresponding to the voltage data. The matching between the processed sensing data SENSE_OUT and the temperature data and the result thereof may be pre-stored.

[0074] can be converted via an analog-to-digital converter ( Figure 2122) and data processing circuit 123 will serve as a temperature sensor ( Figure 2 The digital sensing data D_SENSE of the sensing result of the temperature sensor ( 121) is converted into the processed sensing data SENSE_OUT, and the processed sensing data SENSE_OUT can be stored in the memory 421 in a state matched with the temperature data corresponding to the processed sensing data SENSE_OUT. Figure 2 If a continuous sensing operation is performed in 121), the processed sensing data SENSE_OUT generated in each sensing operation may be stored in the memory 421 together with the temperature data.

[0075] For example, a temperature sensor ( Figure 2 121) can cause V PTAT and can generate V at room temperature PTAT The voltage value of the sensing signal. Figure 2 122) in the memory 421 can digitize the sensing signal, and the data processing circuit 123 can process the digitized sensing signal, thereby generating processed room temperature sensing data ROOM_SENSE_OUT. Here, the room temperature can be about 30° C. The processed room temperature sensing data ROOM_SENSE_OUT can be stored in the memory 421 together with the temperature data of 30° C. (room temperature).

[0076] Optionally, a temperature sensor ( Figure 2 121) can cause V to increase at high temperatures via the temperature sensor circuit. PTAT and can generate V PTAT The voltage value of the sensing signal. Figure 2 122) in the memory 421 can digitize the sensing signal, and the data processing circuit 123 can process the digitized sensing signal, thereby generating processed high temperature sensing data HOT_SENSE_OUT. Here, the high temperature can be about 90° C. The processed high temperature sensing data HOT_SENSE_OUT can be stored in the memory 421 together with the temperature data of 90° C.

[0077] The function generating circuit 422 may read out a plurality of processed sensing data SENSE_OUT and a plurality of temperature data corresponding to the processed sensing data SENSE_OUT from the memory 421 , and may generate a function according to the read out plurality of processed sensing data SENSE_OUT and a plurality of temperature data.

[0078] Figure 6 The process of generating a function using the function generating circuit 422 is shown.

[0079] The function generation circuit 422 can generate a function representing the relationship between temperature and voltage using a plurality of processed sensing data SENSE_OUT and a plurality of temperature data corresponding to the processed sensing data SENSE_OUT. The processed sensing data SENSE_OUT may include a function corresponding to the temperature sensor ( Figure 2 The output V of 121) PTAT If there are two or more temperature data and voltage data corresponding to the temperature data, the function generation circuit 422 can generate a straight line by connecting two or more coordinates on a coordinate plane where the x-axis (TEMP) represents temperature and the y-axis (VPTAT) represents voltage. The function generation circuit 422 can generate a linear function as a straight line on the xy plane, and the linear function can represent the correlation between temperature and voltage. Generating a function by two or more voltage data and two or more temperature data as described above can be called "two-point calibration".

[0080] For example, the processed room temperature sensing data ROOM_SENSE_OUT and the room temperature data corresponding thereto may be stored in the memory 421, and the processed high temperature sensing data HOT_SENSE_OUT and the high temperature data corresponding thereto may be stored in the memory 421. The function generating circuit 422 may generate a linear function as a straight line connecting a point corresponding to the room temperature data and the processed room temperature sensing data ROOM_SENSE_OUT and a relative point corresponding to the high temperature data and the processed high temperature sensing data HOT_SENSE_OUT. For example, the function generating circuit 422 may generate a linear function according to the V at 30°C, 30°C, and 10°C. PTAT , 90℃ and V at 90℃ PTAT A second calibration function 612 is generated. The second calibration function 612 may match an ideal function 620 (indicated by a dashed line). Here, the ideal function 620 (indicated by a dashed line) may represent the desired form of the function generated by the calibration circuit 124. Additionally, the ideal function 620 (indicated by a dashed line) may represent the correlation between temperature and voltage that is the target of the calibration circuit 124.

[0081] Before calibration, the source driver ( Figure 1 120 in the figure) may have a correlation between temperature and voltage such as the basic function 610. Here, the basic function 610 may be a function of the temperature and voltage in manufacturing the source driver ( Figure 1120 in FIG. 124 ) and may be caused by manufacturing defects. Calibration circuit 124 may not seek correlations such as basic function 610. Alternatively, basic function 610 may represent a correlation between temperature and voltage including errors. By two-point calibration of the correlation by calibration circuit 124, instead of a correlation such as basic function 610, source driver ( Figure 1 120) may have a correlation such as an ideal function 620 (indicated by a dashed line). When the calibration circuit 124 performs calibration, it can be understood that the function (correlation) is calibrated as follows.

[0082] For example, the function generation circuit 422 of the calibration circuit 124 may calibrate the slope of the basic function 610 to match the slope of the ideal function 620 (indicated by the dotted line), thereby generating a first calibration function 611. The calibration of the slope may be a first calibration 601, and the slope of the first calibration function 611 and the slope of the ideal function 620 (indicated by the dotted line) may be made the same through the first calibration 601.

[0083] Next, the function generation circuit 422 of the calibration circuit 124 may compensate the y-intercept of the first calibration function 611 to match the y-intercept of the ideal function 620 (indicated by the dashed line), thereby generating a second calibration function 612. The compensation for the y-intercept may be a second calibration 602, which may be referred to as an "offset calibration." The y-intercept of the second calibration function 612 may be made the same as the y-intercept of the ideal function 620 (indicated by the dashed line) by the second calibration 602.

[0084] Finally, the function generation circuit 422 can generate the temperature and voltage V by two calibrations for the slope and y-intercept of the basic function 610. PTAT The second calibration function 612 matches an ideal function 620 (represented by a dashed line) of the desired correlation between .

[0085] Return to reference Figure 4 , the data calculation circuit 125 may apply the new voltage data to the function data FUNCTION, thereby generating new temperature data based on the function data FUNCTION.

[0086] The data calculation circuit 125 may receive the function data FUNCTION from the calibration circuit 124. Here, the function data FUNCTION may be a result obtained by calibrating a function generated by the function generation circuit 422 according to a plurality of processed sensing data SENSE_OUT and temperature data stored in the memory 421. For example, the function generation circuit 422 may generate a second calibration function 612 according to the processed room temperature sensing data ROOM_SENSE_OUT, room temperature data of 30°C, processed high temperature sensing data HOT_SENSE_OUT, and high temperature data of 90°C. The function data FUNCTION may include the second calibration function 612, and the data calculation circuit 125 may receive the second calibration function 612 from the function generation circuit 422.

[0087] The data calculation circuit 125 may generate new temperature data by applying the new voltage data included in the processed sensing data SENSE_OUT to the function data FUNCTION. The data processing circuit 123 may send the processed sensing data SENSE_OUT to both the calibration circuit 124 and the data calculation circuit 125. The data calculation circuit 125 may generate new temperature data according to the function data FUNCTION by applying the voltage data included in the processed sensing data SENSE_OUT to the function data FUNCTION. The new temperature data may be referred to as "calibration temperature data CAL_TEMP_OUT".

[0088] Here, the processed sense data SENSE_OUT including the new voltage data may represent voltage data received by the data calculation circuit 125 other than the processed sense data SENSE_OUT stored in the memory 421 for use in generating the function. The data calculation circuit 125 may calculate new temperature data by applying the new voltage data to the pre-generated function. Here, the new voltage data may be referred to as "input voltage data", and the new temperature data may be referred to as "output temperature data".

[0089] Specifically, the data calculation circuit 125 may apply the voltage data included in the processed sensing data SENSE_OUT to the second calibration function 612 included in the function data FUNCTION, thereby calculating the calibration temperature data CAL_TEMP_OUT. Here, the processed sensing data SENSE_OUT applied to the second calibration function 612 may be the same as or different from the processed sensing data SENSE_OUT used in the generation of the second calibration function 612. That is, if the second calibration function 612 is generated based on the processed room temperature sensing data ROOM_SENSE_OUT and the processed high temperature sensing data HOT_SENSE_OUT, the processed sensing data SENSE_OUT applied to the second calibration function 612 may be one of the processed room temperature sensing data ROOM_SENSE_OUT and the processed high temperature sensing data HOT_SENSE_OUT, or may be processed sensing data SENSE_OUT other than the processed room temperature sensing data ROOM_SENSE_OUT and the processed high temperature sensing data HOT_SENSE_OUT.

[0090] For example, if the data calculation circuit 125 calculates V corresponding to a room temperature of 30°C PTAT The calibration temperature data CAL_TEMP_OUT corresponding to the room temperature may be generated by applying the second calibration function 612. The calibration temperature data CAL_TEMP_OUT may represent a temperature of 30°C. Alternatively, if the data calculation circuit 125 converts the V corresponding to the high temperature of 90°C to PTAT Applied to the second calibration function 612, calibration temperature data CAL_TEMP_OUT corresponding to the high temperature may be generated. The calibration temperature data CAL_TEMP_OUT may represent a temperature of 90°C.

[0091] The data calculation circuit 125 applies the processed sense data SENSE_OUT to the basic function 610 before calibration, and applies the processed sense data SENSE_OUT to the second calibration function 612 after calibration. Therefore, the temperature data output before calibration and the calibration temperature data CAL_TEMP_OUT after calibration may be different from each other. Here, it can be understood that the temperature data output before calibration contains an error reflected in the temperature data, but the calibration temperature data CAL_TEMP_OUT after calibration has no error, which has been removed from the calibration temperature data CAL_TEMP_OUT.

[0092] The source driver 120 according to the present invention can find an ideal linear function between temperature and voltage, and can match the existing correlation (function) to the ideal linear function, thereby correcting the temperature value. In addition, the source driver 120 according to the present invention can use two arbitrary points that do not satisfy specific conditions such as a sequence, but rather correlate the digitally represented temperature and voltage, and can store the data required for calibration in a storage device and use the data. Therefore, the present invention can provide a high-accuracy error reduction effect by a simple method.

[0093] The data output circuit 126 may output the calibration temperature data CAL_TEMP_OUT and the new temperature value corresponding thereto. Before outputting the data, the data output circuit 126 may process the calibration temperature data CAL_TEMP_OUT and then may output the calibration temperature data CAL_TEMP_OUT. For example, the data output circuit 126 may reduce the number of bits of the calibration temperature data CAL_TEMP_OUT. In the case where the processed sense data SENSE_OUT is configured as 16 bits, the data output circuit 126 may reduce the calibration temperature data CAL_TEMP_OUT to 8 bits by removing the digits after the decimal point and then may output the calibration temperature data CAL_TEMP_OUT.

[0094] Figure 7 is a diagram illustrating a process of differently selecting data according to a display mode in a calibration circuit according to another embodiment.

[0095] refer to Figure 7 , the calibration circuit 724 may selectively use the stored processed sensing data SENSE_OUT according to the display mode, thereby performing different calibration processes.

[0096] Even if the source driver ( Figure 1 120 in FIG. 120) outputs calibration temperature data according to the correlation (eg, function) between temperature and voltage, and the calibration temperature data may also contain errors caused by several factors. For example, the temperature sensor ( Figure 2 The ground voltage of the temperature sensor (121) may increase, and if the ground voltage increases, the temperature sensor ( Figure 2 121) in V generated PTAT may vary and is based on V PTAT The output temperature data may not properly reflect the source driver ( Figure 1 The actual temperature of the source driver ( Figure 1 The power consumption of 120) in the circuit or the change of parasitic resistance caused by the wire may cause the change of ground voltage.

[0097] As another example, if the source driver ( Figure 1 120) consumes a lot of power, the source driver ( Figure 1 The internal temperature of the 120 in the may increase. If the internal temperature increases, the temperature sensor ( Figure 2 121) in V generated PTAT may vary and is based on V PTAT The output temperature data may not properly reflect the source driver ( Figure 1 120) of the actual temperature (e.g., Figure 1 The external temperature of the source driver 120 in FIG.

[0098] As described above, the source driver ( Figure 1 The power consumption of the source driver ( 120 ) can define the display mode according to whether the amount of power consumption is large or small. The display mode can include a high power mode and a low power mode. The high power mode can mean that the source driver ( Figure 1 The low power mode may indicate that the source driver ( Figure 1 120) in the case where the device operates while consuming a small amount of power.

[0099] On the other hand, the display mode can be set according to the source driver ( Figure 1 The driving mode of 120) varies.

[0100] For example, if the panel outputs images at a high refresh rate (RR), the source driver ( Figure 1 120 in the source driver always supplies a constant data voltage to the panel, so the source driver ( Figure 1 The amount of power consumed by the source driver (120 in FIG. 120 ) and the corresponding amount of heat generated may increase, which may also increase the source driver ( Figure 1 120) temperature. Including source driver ( Figure 1 120) of the display device ( Figure 1 100) is in high power mode (driving mode). At this time, only the display device ( Figure 1 100) internal source driver ( Figure 1 The temperature of 120) in the reactor is locally high.

[0101] On the other hand, if the panel outputs images at a low refresh rate, the source driver ( Figure 1 120 in the high refresh state) supplies the data voltage in a relatively less continuous manner than in the high refresh state, thereby reducing the source driver ( Figure 1 120 in the example) and the corresponding amount of power consumed and the corresponding amount of heat generated, and can also reduce the source driver ( Figure 1120) temperature. Including source driver ( Figure 1 120) of the display device ( Figure 1 100 in the figure) can be in low power mode (standby mode). At this time, only the display device ( Figure 1 100) internal source driver ( Figure 1 The temperature of 120) in the region is locally low.

[0102] Source Driver( Figure 1 120) in the temperature (ie, display mode) may affect the temperature sensor ( Figure 2 Therefore, the temperature sensor ( Figure 2 The error in 121) can be calculated based on the source driver ( Figure 1 For example, the temperature sensor ( Figure 2 121) can sense a source driver ( Figure 1 Therefore, the source driver ( Figure 1 The calibration circuit 724 of 120 in the display unit 120 needs to be calibrated differently between the high power mode and the low power mode. The calibration circuit 724 can selectively read out the data used for calibration in each display mode according to the display mode, thereby using the data for calibration.

[0103] For differentiated calibration depending on the display mode, the calibration circuit 724 may read different data from the memory 721 according to the display mode, and may generate a function using the read data. Here, the processed sensing data SENSE_OUT (voltage data) may be stored in the memory 721 together with the temperature data corresponding to the processed sensing data SENSE_OUT in a state matched with the temperature data, and may be read out from the memory 721.

[0104] For example, for each display mode, the processed sensing data SENSE_OUT may be stored in the memory 721. The display mode may include a high power mode and a low power mode. The high power mode may indicate that the source driver ( Figure 1 120) in the case where the amount of power consumed by and the heat generated by the source driver ( Figure 1Therefore, the following processed sensing data SENSE_OUT may be stored in the memory 721: such as the processed high-power room temperature sensing data H_ROOM_SENSE_OUT and the processed high-power high-temperature sensing data H_HOT_SENSE_OUT used in the high-power mode, and such as the processed low-power room temperature sensing data L_ROOM_SENSE_OUT and the processed low-power high-temperature sensing data L_HOT_SENSE_OUT used in the low-power mode.

[0105] The calibration circuit 724 may select different processed sensing data SENSE_OUT via the MUXs 701 and 702 according to the display mode.

[0106] MUX 701 and 702 may include: a first MUX 701 for receiving inputs of processed high power room temperature sensing data H_ROOM_SENSE_OUT and processed low power room temperature sensing data L_ROOM_SENSE_OUT; and a second MUX 702 for receiving inputs of processed high power high temperature sensing data H_HOT_SENSE_OUT and processed low power high temperature sensing data L_HOT_SENSE_OUT.

[0107] MUX 701 and 702 may receive a mode selection signal MODE_SEL. The mode selection signal MODE_SEL may control MUX 701 and 702 to select the source driver ( Figure 1 The display mode of the display circuit 120 in FIG. 120 is used to select different processed sensing data SENSE_OUT from the memory 721. The function generating circuit 422 included in the mode selector (not shown) or the calibration circuit 724 may transmit the mode selection signal MODE_SEL to the MUXs 701 and 702.

[0108] For example, if the MUXs 701 and 702 receive a mode selection signal MODE_SEL for selecting the first mode, the first MUX 701 may read out the processed high-power room temperature sensing data H_ROOM_SENSE_OUT from the memory 721, and the second MUX 702 may read out the processed high-power high-temperature sensing data H_HOT_SENSE_OUT from the memory 721. Alternatively, if the MUXs 701 and 702 receive a mode selection signal MODE_SEL for selecting the second mode, the first MUX 701 may read out the processed low-power room temperature sensing data L_ROOM_SENSE_OUT from the memory 721, and the second MUX 702 may read out the processed low-power high-temperature sensing data L_HOT_SENSE_OUT from the memory 721.

[0109] The function generating circuit 422 may receive the processed sensing data SENSE_OUT from the MUXs 701 and 702 and may output calibration temperature data CAL_TEMP_OUT by generating a function.

[0110] For example, if MUX 701 and 702 receive a mode selection signal MODE_SEL for selecting a first mode, the function generation circuit 422 may generate a function according to the processed high-power room temperature sensing data H_ROOM_SENSE_OUT and the processed high-power high-temperature sensing data H_HOT_SENSE_OUT, and may compensate the slope and y-axis intercept of the function, thereby generating a compensation function. The data calculation circuit 125 may calculate the calibration temperature data CAL_TEMP_OUT by applying the processed sensing data SENSE_OUT to the compensation function. Alternatively, if MUX 701 and 702 receive a mode selection signal MODE_SEL for selecting a second mode, the function generation circuit 422 may generate a function according to the processed low-power room temperature sensing data L_ROOM_SENSE_OUT and the processed low-power high-temperature sensing data L_HOT_SENSE_OUT. The function may be generated by calibrating the slope and y-axis intercept of the function. The data calculation circuit 125 may calculate calibration temperature data CAL_TEMP_OUT by applying the processed sense data SENSE_OUT to the function.

[0111] Although it has been described in the above embodiments that the first mode represents the high power mode and the second mode represents the low power mode, the first mode may represent the low power mode and the second mode may represent the high power mode according to the connection method or characteristics of the mode selection signal MODE_SEL.

[0112] As described above, according to the driving of the panel, the source driver ( Figure 1 120) to use data differently based on the power consumption (or display mode) of the source driver ( Figure 1 Any difference between the sensed temperature and the actual temperature caused by the power consumption (heat) of 120).

[0113] Figure 8 is a diagram illustrating a process of selecting offset reflection data according to a display mode in a calibration circuit according to another embodiment.

[0114] refer to Figure 8 , the calibration circuit 824 may use the processed sensing data SENSE_OUT reflecting the offset in the calibration process. The reflection of the offset may include adding a specific value to the data or subtracting a specific value from the data. In addition, the offset may be mainly reflected in the voltage data of the processed sensing data SENSE_OUT. Hereinafter, the processed sensing data SENSE_OUT (voltage data) may be stored in the memory 821 together with the temperature data in a manner matching the corresponding temperature data, or the processed sensing data SENSE_OUT (voltage data) may be read out from the memory 821.

[0115] The processed sensing data SENSE_OUT may be stored in the memory 821 for each display mode, and the offset data SENSE_OFFSET may also be stored in the memory 821 .

[0116] The calibration circuit 824 may add the offset data SENSE_OFFSET to the processed sensing data SENSE_OUT stored in the memory 821 via adders 805 and 806. Alternatively, the calibration circuit 824 may subtract the offset data SENSE_OFFSET from the processed sensing data SENSE_OUT stored in the memory 821 via a subtractor (not shown).

[0117] The calibration circuit 824 may reflect the offset data SENSE_OFFSET to the processed sensing data SENSE_OUT corresponding to any one display mode.

[0118] For example, adders 805 and 806 may reflect only the offset data SENSE_OFFSET to the processed sensing data SENSE_OUT in low power mode. Adders 805 and 806 may add the offset value of the offset data SENSE_OFFSET to the processed low power room temperature sensing data L_ROOM_SENSE_OUT, and may add the offset value to the processed low power high temperature sensing data L_HOT_SENSE_OUT. Optionally, adders 805 and 806 may also reflect the offset data SENSE_OFFSET to the processed sensing data SENSE_OUT in high power mode. Adders 805 and 806 may add the offset value of the offset data SENSE_OFFSET to the processed high power room temperature sensing data H_ROOM_SENSE_OUT, and may add the offset value to the processed high power high temperature sensing data H_HOT_SENSE_OUT.

[0119] The calibration circuit 824 may select the processed sensing data SENSE_OUT reflecting the offset via the MUXs 803 and 804 according to the display mode.

[0120] MUX 803 and 804 may include: a third MUX 803 for receiving inputs of processed high-power room temperature sensing data H_ROOM_SENSE_OUT and processed low-power room temperature sensing data L_ROOM_SENSE_OUT to which offset data SENSE_OFFSET is added; and a fourth MUX 804 for receiving inputs of processed high-power high-temperature sensing data H_HOT_SENSE_OUT and processed low-power high-temperature sensing data L_HOT_SENSE_OUT to which offset data SENSE_OFFSET is added.

[0121] MUX 803 and 804 may receive an offset selection signal OFFSET_SEL. The offset selection signal OFFSET_SEL may control MUX 803 and 804 to select the offset of the display device ( Figure 1 The processed sensing data SENSE_OUT reflecting the offset data SENSE_OFFSET is selected from the memory 821 according to the display mode of 100 in FIG. The function generating circuit 422 included in the offset selector (not shown) or the calibration circuit 824 may send the offset selection signal OFFSET_SEL to the MUXs 803 and 804.

[0122] For example, if the MUXs 803 and 804 receive an offset selection signal OFFSET_SEL for selecting the offset reflection data, the third MUX 803 may read out the processed low power room temperature sensing data L_ROOM_SENSE_OUT to which the offset data SENSE_OFFSET is added from the memory 821, and the fourth MUX 804 may read out the processed low power high temperature sensing data L_HOT_SENSE_OUT to which the offset data SENSE_OFFSET is added from the memory 821. Alternatively, if the MUXs 803 and 804 receive an offset selection signal OFFSET_SEL for not selecting the offset reflection data, the third MUX 803 may read out the processed high power room temperature sensing data H_ROOM_SENSE_OUT from the memory 821, and the fourth MUX 804 may read out the processed high power high temperature sensing data H_HOT_SENSE_OUT from the memory 821.

[0123] MUX 801 and 802 can be used with Figure 7 The MUXs 701 and 702 shown have the same functions, but differ in that one of the input terminals is connected to the output terminals of the MUXs 803 and 804. Therefore, if the MUXs 801 and 802 receive the mode selection signal MODE_SEL for selecting the first mode, the first MUX 801 may output the data output from the third MUX 803 (the processed high-power room temperature sensing data H_ROOM_SENSE_OUT or the processed low-power room temperature sensing data L_ROOM_SENSE_OUT to which the offset data SENSE_OFFSET is added), and the second MUX 802 may output the data output from the fourth MUX 804 (the processed high-power high-temperature sensing data H_HOT_SENSE_OUT or the processed low-power high-temperature sensing data L_HOT_SENSE_OUT to which the offset data SENSE_OFFSET is added).

[0124] The function generation circuit 422 may generate a function using the processed sensing data SENSE_OUT finally output from the MUXs 801 and 802 .

[0125] As described above, the calibration circuit 824 may select different data according to the high power mode and the low power mode according to the driving of the panel, and may further select data reflecting the offset data SENSE_OFFSET for either mode, thereby generating the calibration temperature data CAL_TEMP_OUT. Figure 8It is shown that the offset data SENSE_OFFSET is reflected in the processed low power room temperature sensing data L_ROOM_SENSE_OUT and the processed low power high temperature sensing data L_HOT_SENSE_OUT used in the low power mode, but the present invention is not limited to this, and the offset data SENSE_OFFSET may also be reflected in the processed high power room temperature sensing data H_ROOM_SENSE_OUT and the processed high power high temperature sensing data H_HOT_SENSE_OUT used in the high power mode.

[0126] Fig. 9 is a diagram showing a structure of a display device according to another embodiment.

[0127] refer to Fig. 9 , the display device 900 may include a chip on film (COF) package 910 .

[0128] The chip on film package 910 may have a semiconductor chip (eg, source driver 120) mounted thereon. The source driver 120 may receive image data from a timing controller 140 disposed in the circuit board 920 via a first line L1, and may output a data driving signal to the panel 110 via a second line L2.

[0129] The source driver 120 included in the COF package 910 may sense the temperature of the panel 110 via the temperature sensor 121. The structure in which the COF package 910 and the panel 110 are coupled to each other may enable the source driver 120 to sense the temperature of the panel 110.

[0130] The temperature of the panel 110 may be independent of the voltage data and the temperature data used in the process of calibrating the source driver 120. That is, the temperature of the panel 110 may not be used to generate the second calibration function ( Figure 6 612) and stored in memory ( Figure 4 The source driver 120 can sense the temperature of the panel 110 via the temperature sensor 121, and can generate the temperature data in the second calibration function ( Figure 6 The source driver 120 may output new temperature data as 612 in FIG.

[0131] For reference, the calibration may be performed in the process of manufacturing or testing the source driver 120. Preferably, the calibration may be performed before the source driver 120 is coupled to the chip-on-film package 910.

[0132] If the chip-on-film package 910 is attached or coupled to any surface of the panel 110 to contact therewith, the heat of the panel 110 may be transferred to the surface. Due to the heat transfer from the panel 110 to the chip-on-film package 910, the temperature of the chip-on-film package 910 may be almost the same as the temperature of the panel 110. Since the source driver 120 is included in the chip-on-film package 910, the temperature of the source driver 120 may also be almost the same as the temperature of the panel 110. The source driver 120 may output a calibration temperature through the above-mentioned calibration process, and the calibration temperature may be regarded as the temperature of the panel 110.

[0133] The chip-on-film package 910 may be coupled to the entire area of ​​one surface of the panel 110. The large coupling area may facilitate heat transfer from the panel 110 to the chip-on-film package 910, so that the temperature of the chip-on-film package 910 (i.e., the temperature of the source driver 120) may be close to the temperature of the panel 110. Fig. 9 As shown, if the COF package 910 is coupled to a portion of one surface of the panel 110 such that the entire area of ​​the COF package 910 contacts the portion, the temperature of the source driver 120 may be close to the temperature of the panel 110 .

[0134] Fig.10 is a cross-sectional view illustrating an example of coupling between a source driver and a panel according to another embodiment.

[0135] refer to Fig.10 The chip-on-film package 910 may include a source driver 120 , an insulating layer 1011 , a metal line layer 1012 , a film layer 1013 , a bumper 1014 , and a heat sink 1015 .

[0136] The insulating layer 1011 may be located on the metal wire layer 1012, thereby improving the insulation of the metal wire layer 1012 and protecting the metal wire from the outside. The insulating layer 1011 may include a so-called surface resist (SR) material.

[0137] The metal line layer 1012 may be formed of a plurality of metal lines to be arranged on the thin film layer 1013. The metal line layer 1012 may include a first line (see Fig. 9 L1 in) and the second line (see Fig. 9 in L2).

[0138] The metal line layer 1012 may be formed of a metal material such as copper, etc., and may be electrically connected to the source driver 120 via the buffer 1014 .

[0139] The thin film layer 1013 as a flexible film may be a polyimide-based flexible film.

[0140] The buffer 1014 may be formed on a lower surface of the source driver 120 and may be coupled to an exposed portion of the metal wire layer 1012 (ie, a portion where the insulating layer 1011 is not formed), thereby electrically connecting the source driver 120 and the metal wire layer 1012 .

[0141] The heat sink 1015 may be inserted between the thin film layer 1013 and the panel 110, and may facilitate heat transfer between the source driver 120 and the panel 110. Since the heat sink 1015 includes a heat sink metal made of a metal material such as aluminum, the heat sink 1015 may have high thermal conductivity. The heat of the panel 110 may be transferred to the source driver 120 via the heat sink 1015, the thin film layer 1013, the metal wire layer 1012, and the buffer 1014 (see the dotted arrow).

[0142] If the chip-on-film package 910 is attached to or in contact with the panel 110 with the heat sink 1015 as a boundary between the chip-on-film package 910 and the panel 110, the heat of the panel 110 may be transferred to the source driver 120. The temperature of the source driver 120 may be the same as the temperature of the panel 110, and according to an embodiment of the present invention, the source driver 120 may sense the temperature and may output a calibrated temperature. The heat sink 1015 inserted between the source driver 120 and the panel 110 may help the source driver 120 to accurately identify the temperature of the panel 110.

[0143] Fig.11 is a diagram showing a first example of experimental results for calibration of temperature according to an embodiment of the present invention.

[0144] Fig.11 A table comparing the calibration temperature output through the calibration process according to the embodiment of the present invention with the actual temperature is shown.

[0145] When the first sample (sample 1) and the second sample (sample 2) are placed in a chamber and the temperature of the chamber is sequentially set to -20°C, 0°C, 10°C, 20°C, 30°C, 40°C, 50°C, and 90°C, the calibration temperatures of the first sample and the second sample are almost the same as the actual temperature of the chamber. The first sample and the second sample may be used to implement the source driver ( Figure 1 120 in ), or may be a display device including these source drivers ( Figure 1 of 100).

[0146] The first sample showed the same value at -20°C, 0°C, 10°C and 20°C, but had an error of about 1°C in some intervals. The second sample also showed the same value at 0°C, 10°C, 20°C and 30°C, but had an error of about 1°C in some intervals.

[0147] Fig.12 is a diagram showing a second example of experimental results for calibration of temperature according to an embodiment of the present invention.

[0148] Fig.12 A graph comparing a calibration temperature output through a calibration process according to an embodiment of the present invention with an actual temperature is shown.

[0149] This graph is obtained by comparing the average value (denoted as "result") of the calibration temperature outputted 5 times (N=5) from the sample placed in the chamber while continuously configuring the temperature of the chamber with the actual temperature of the chamber (denoted as "chamber temperature"). The graph shows that the average calibration temperature value of the sample matches the actual temperature value of the chamber.

[0150] Fig.13 is a graph showing a third example of experimental results for calibration of temperature according to an embodiment of the present invention.

[0151] Fig.13 A graph representing the difference between a calibration temperature output through a calibration process according to an embodiment of the present invention and an actual temperature is shown.

[0152] The graph shows that when the temperature of the chamber is continuously configured, the calibration temperature output from the sample placed in the chamber has a difference of about 0.2°C (denoted as "Result") in some intervals compared to the actual temperature of the chamber (denoted as "Chamber Temperature"), but the difference decreases from a temperature of 10°C and eventually becomes the same as the actual temperature.

[0153] Fig.14 is a diagram showing a first example of a conventional temperature sensing error, and Fig.15 is a diagram showing a second example representing a conventional temperature sensing error.

[0154] Fig.14 and Fig.15 A graph showing the number of samples (denoted as "Number of Samples") outputting actual temperatures according to temperatures (denoted as "Output") outputted from a group of products manufactured according to the prior art is shown.

[0155] exist Fig.14 In an environment where the actual temperature is 30°C, conventional products (source drivers or display devices) can output temperatures within an error range of 28°C to 32°C. Most products output values ​​of 29.8°C, 30.25°C, and 30.7°C, which are very different from the actual temperature of 30°C. This may indicate that the temperature sensing function of the prior art is relatively inaccurate.

[0156] exist Fig.15In an environment where the actual temperature is 90°C, conventional products (source drivers or display devices) can output temperatures within an error range of 86°C to 97°C. Most products output values ​​of 90.1°C, 91.3°C, 92.4°C, and 93.6°C, which are very different from the actual temperature of 90°C. This may also indicate that the temperature sensing function of the prior art is relatively inaccurate.

[0157] CROSS-REFERENCE TO RELATED APPLICATIONS

[0158] This application claims priority to Korean Patent Application No. 10-2019-0113249, filed on September 16, 2019, which is hereby incorporated by reference for all purposes as if fully set forth herein.

Claims

1. A source driver, comprising: a calibration circuit configured to differently obtain a plurality of temperature data and a plurality of voltage data corresponding to the plurality of temperature data according to respective modes depending on the power consumption of the source driver, and generate a function between temperature and voltage for a corresponding mode according to the obtained plurality of temperature data and the obtained plurality of voltage data; as well as a data calculation circuit configured to determine the mode of the source driver according to the calculated calibration temperature data, receive input voltage data, select a function corresponding to the mode of the source driver and apply the input voltage data to the selected function, thereby calculating temperature data corresponding to the input voltage data, The modes include a first mode for a first power consumption and a second mode for a second power consumption lower than the first power consumption.

2. The source driver according to claim 1, wherein: The source driver further includes a memory configured to store a first plurality of temperature data and a first plurality of voltage data according to the first mode, and a second plurality of temperature data and a second plurality of voltage data according to the second mode.

3. The source driver according to claim 2, wherein: The calibration circuit is configured to read out a plurality of temperature data and a plurality of voltage data from the memory according to the mode, and to generate the function according to the read plurality of temperature data and the read plurality of voltage data.

4. The source driver according to claim 1, wherein: The power consumption is determined by the refresh rate RR of the panel.

5. The source driver according to claim 1, further comprising a memory configured to store offset data, wherein: The calibration circuit is configured to generate the function according to data obtained by reflecting the offset data to the plurality of voltage data.

6. The source driver according to claim 5, wherein: The calibration circuit includes a multiplexer (MUX) configured to select the plurality of voltage data or the offset data. 7 . The source driver of claim 1 , further comprising a temperature sensor configured to generate a signal corresponding to the plurality of voltage data and the input voltage data.

8. A display device, comprising: panel; as well as a source driver coupled to one surface of the panel and configured to: receive heat from the panel, obtain temperature data and voltage data differently according to each mode depending on power consumption of the source driver, obtain first temperature data, first voltage data corresponding to the first temperature data, second temperature data, and second voltage data corresponding to the second temperature data according to a first mode, obtain third temperature data, third voltage data corresponding to the third temperature data, fourth temperature data, and fourth voltage data corresponding to the fourth temperature data according to a second mode, generate a first function between temperature and voltage according to the first temperature data, the first voltage data, the second temperature data, and the second voltage data, generate a second function between temperature and voltage according to the third temperature data, the third voltage data, the fourth temperature data, and the fourth voltage data, determine whether the mode of the source driver is the first mode or the second mode according to the calculated calibration temperature data, select a function corresponding to the mode of the source driver, receive fifth voltage data, and calculate fifth temperature data corresponding to the fifth voltage data by applying the fifth voltage data to the selected function, The power consumption of the first mode is greater than the power consumption of the second mode. 9 . The display device according to claim 8 , further comprising a heat dissipation plate located between the panel and the source driver to transfer heat from the panel to the source driver.

10. The display device according to claim 8, wherein: The fifth temperature data is the temperature of the panel.

11. A source driver, comprising: a calibration circuit configured to differently obtain temperature data and voltage data according to modes depending on power consumption of the source driver, obtain first temperature data, first voltage data corresponding to the first temperature data, second temperature data, and second voltage data corresponding to the second temperature data according to a first mode, obtain third temperature data, third voltage data corresponding to the third temperature data, fourth temperature data, and fourth voltage data corresponding to the fourth temperature data according to a second mode, generate a first function between temperature and voltage according to the first temperature data, the first voltage data, the second temperature data, and the second voltage data, and generate a second function between temperature and voltage according to the third temperature data, the third voltage data, the fourth temperature data, and the fourth voltage data; as well as a data calculation circuit configured to determine whether the mode of the source driver is the first mode or the second mode according to the calculated calibration temperature data, select a function corresponding to the mode of the source driver, and receive fifth voltage data, and calculate fifth temperature data corresponding to the fifth voltage data by applying the fifth voltage data to the selected function, The power consumption of the first mode is greater than the power consumption of the second mode.

12. The source driver according to claim 11, further comprising a memory configured to store data, wherein: The calibration circuit is configured to read out the first to fourth temperature data and the first to fourth voltage data from the memory. 13 . The source driver of claim 11 , further comprising a temperature sensor configured to generate first to fifth analog signals corresponding to the first to fifth voltage data according to temperature. 14 . The source driver according to claim 13 , further comprising an analog-to-digital converter configured to digitize the first to fifth analog signals into the first to fifth voltage data.

15. The source driver according to claim 11, wherein: The first function is a linear function obtained by combining the first temperature data, the first voltage data, the second temperature data and the second voltage data, and the second function is a linear function obtained by combining the third temperature data, the third voltage data, the fourth temperature data and the fourth voltage data.

16. The source driver according to claim 15, wherein: The calibration circuit is configured to generate the function by adjusting a slope of the function and an offset of the function.

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