TWI545545B - Source driving method and circuit for electro-phoretic display - Google Patents

Description

Source driving method and circuit applied to electrophoretic display

The present invention relates to a driving circuit, and more particularly to a source driving method and circuit applied to an electrophoretic display.

An electro-phoretic display (EPD) is a display device that can control the movement of colored charged particles by an electric field in an electrophoresis system such as a microcapsule to display an image. The electrophoretic display has the characteristics of power saving, no need for backlighting, and the fact that the screen does not disappear after power-off, and has been widely used in various fields.

The existing electrophoretic display can be driven by an active matrix, including an upper and a lower substrate, a TFT driving circuit and a common electrode respectively disposed on the upper and lower substrates, and an electrophoretic layer interposed between the upper and lower substrates. The TFT driving circuit receives the scanning signal to turn on each pixel, so that the turned-on pixel corresponds to the receiving pixel voltage; the common electrode receives the common voltage for biasing the pixel voltage of each pixel to form a specific electric field to change. The position of the colored charged particles in the electrophoretic structure layer, thereby displaying a gray scale picture.

The above pixel voltage is generally output by the source driving circuit according to the input picture data. However, the pixel voltage output by the source driver circuit often needs to be switched between various voltage levels, for example, switching between two different positive voltage levels, between two different negative voltage levels, or in a positive Switching between voltage level and a negative voltage level often results in Some non-ideal effects and extra power loss.

For example, when the pixel voltage is switched between two different positive voltage levels (or between two different negative voltage levels), the load effect causes the two voltage levels to converge (loading on the load). The highest or lowest voltage slowly pulls the next high voltage high or pulls the second low voltage low, causing display errors. When the pixel voltage output is switched between a positive voltage level and a negative voltage level, the positive voltage level is directly switched to the negative voltage level or directly switched from the negative voltage level to the positive voltage level. It will cause additional power loss.

Therefore, it is necessary to provide a source driving method and circuit for an electrophoretic display to solve the problems of the conventional technology.

The main object of the present invention is to provide a source driving method for an electrophoretic display, which inserts a third voltage when the source voltage is switched between two different voltage levels to reduce the known non-ideal effect or Power consumption enables the electrophoretic display to achieve better display and extend its life.

To achieve the above object, the present invention provides a source driving method applied to an electrophoretic display, the source driving method comprising the steps of: receiving write data; outputting a corresponding source voltage according to the written data; comparing by a logic control unit Whether the written data received in the previous timing and the written data received in the subsequent timing satisfy a predetermined difference value; when the predetermined difference value is received between the currently received timing data, a control signal is output; and the control signal is output according to the control signal a corresponding third voltage is used instead of the source voltage corresponding to the output corresponding to the write data received according to the previous timing; and the corresponding source voltage is outputted by the write data that ends the control signal and is received according to the latter timing.

In an embodiment of the invention, the step of receiving the written data is through a a temporary storage unit and a second temporary storage unit capture and store the write data from a timing controller in a latching manner, wherein the write data stored by the first temporary storage unit is defined as a first write data; The second temporary storage unit captures the first write data output by the first temporary storage unit to be stored as a second write data, and the second write data is used in the next timing with the first temporary storage unit. The stored first written data is compared.

In an embodiment of the present invention, the write data received by the current post-timing corresponds to no When the voltage level corresponding to the same polarity voltage level and the write data received by the latter timing is lower, the voltage level of the third voltage is lower than the voltage level corresponding to the written data received by the latter timing. .

In an embodiment of the invention, the voltage level of the third voltage is zero voltage level.

In an embodiment of the present invention, when the write data received by the current post-timing corresponds to different voltage levels of the same polarity and the voltage level corresponding to the write data received by the latter timing is higher, the voltage of the third voltage is The bit level is higher than the voltage level corresponding to the written data received by the latter timing.

In an embodiment of the present invention, when the write data received by the current post-timing corresponds to a voltage level of different polarities, the voltage level of the third voltage is between the voltage level corresponding to the currently written data and the previous write. Enter the voltage level corresponding to the data.

In an embodiment of the invention, the voltage level of the third voltage is zero voltage level.

The invention further provides a source driving circuit applied to an electrophoretic display, the package thereof Included: a first temporary storage unit (LH1) for receiving a first latch enable signal (le1) for capturing a write data and storing it as a first write data (data1); a temporary storage unit (LH2) for receiving a second latch enable signal (le2) for capturing the first write data and storing the second write data (data2); a logic control unit (logic Detecting, the first temporary storage unit and the second temporary storage unit are configured to determine whether the first written data and the second written data satisfy a predetermined difference value, and satisfy the predetermined difference Outputting a control signal (act); a decoding unit is coupled to the second temporary storage unit and the logic control unit, and the decoding unit directly outputs the second written data, or receives the When the logic control unit controls the signal, the second write data is rewritten into a temporary write data according to the control signal; and a switch unit is coupled to the decoding unit to receive the second write data or the temporary write Input data, which outputs a corresponding source according to the second write data , Or a third voltage corresponding to the output based on the written data temporarily.

In an embodiment of the present invention, the method further includes coupling to the logic control unit and the A third temporary storage unit between the decoding units, the third temporary storage unit captures and stores the control signal output by the logic control unit when receiving a third latch enable signal, and outputs the control signal to the decoding unit.

In an embodiment of the present invention, the method further includes coupling to the logic control unit and the a third temporary storage unit between the second temporary storage unit, the third temporary storage unit extracting the second written data output by the second temporary storage unit according to the first latch enable signal to store the first Third, writing data, and outputting the third write data to the logic control unit; the logic control unit determines whether a predetermined difference value is satisfied between the first write data and the third write data, and The aforementioned control signal is output when the predetermined difference value is satisfied.

In an embodiment of the present invention, when the first write data and the second write resource The voltage level of the third voltage is lower than the voltage corresponding to the second written data when the voltage level corresponding to the same polarity is corresponding to the voltage level corresponding to the written data received by the second write data. Voltage level.

In an embodiment of the invention, the voltage level of the third voltage is zero voltage level.

In an embodiment of the present invention, when the first write data and the second write data correspond to different voltage levels of the same polarity and the voltage level corresponding to the second write data is higher, the third The voltage level of the voltage is higher than the voltage level corresponding to the second write data.

In an embodiment of the present invention, when the first write data and the second write data correspond to voltage levels of different polarities, the voltage level of the third voltage is corresponding to the first write data. The voltage level is between the voltage level corresponding to the second write data.

In an embodiment of the invention, the voltage level of the third voltage is zero voltage level.

In summary, the present invention mainly compares the difference between the previously written data by the logic control unit to temporarily insert a third voltage when the source voltage is switched between two different voltage levels. Compared with directly switching the source voltage from the current level to the next level, the present invention temporarily inserts the third voltage to reduce the known non-ideal effect or power consumption, so that the electrophoretic display achieves better display effect. And can extend its service life.

LH1‧‧‧First temporary storage unit

LH2‧‧‧Second temporary storage unit

10‧‧‧Logical Control Unit

11‧‧‧Decoding unit

SW‧‧‧Switch unit

Swp1, swp2, swpn‧‧‧ positive voltage switch

Sw0‧‧ ‧ zero voltage switch

Swn1, swpn2, swnn‧‧‧ negative voltage switch

1 is a block diagram showing an output of a source driving circuit applied to an electrophoretic display according to a preferred embodiment of the present invention; 2A-2C are schematic diagrams showing changes in signal waveforms after a third driving voltage is applied to a source driving circuit of an electrophoretic display according to a preferred embodiment of the present invention; FIG. 3 is a first preferred embodiment of the present invention. A circuit block diagram of a source driving circuit applied to an electrophoretic display; FIG. 4 is a signal waveform diagram of an output end of the source driving circuit of FIG. 3; and FIG. 5 is an application according to a second preferred embodiment of the present invention. A block diagram of a circuit of a source driving circuit of an electrophoretic display; FIG. 6 is a signal waveform diagram of an output end of the source driving circuit of FIG. 5; and FIG. 7 is a circuit diagram for electrophoresis according to a third preferred embodiment of the present invention. A circuit block diagram of a source driving circuit of the display; FIG. 8 is a signal waveform diagram of an output end of the source driving circuit of FIG. 7; and FIG. 9 is a source of an electrophoretic display according to a preferred embodiment of the present invention; Flow chart of the driving method.

The above and other objects, features and advantages of the present invention will become more <RTIgt; Furthermore, the directional terms mentioned in the present invention, such as upper, lower, top, bottom, front, rear, left, right, inner, outer, side, surrounding, central, horizontal, horizontal, vertical, longitudinal, axial, Radial, uppermost or lowermost, etc., only refer to the direction of the additional schema. Therefore, the directional terminology used is for the purpose of illustration and understanding of the invention.

The present invention provides a source driving circuit applied to an electrophoretic display. The electrophoretic display generally includes a timing controller, a scan driving circuit, the source driving circuit, and electrophoresis Main components such as panels. The timing controller is configured to receive screen data of a display screen and output corresponding display materials accordingly. The scan driver circuit and the source driver circuit are coupled to the timing controller, wherein the timing controller controls the scan driver circuit to sequentially output a plurality of scan signals to sequentially turn on each pixel unit of the electrophoresis panel; The pole drive circuit receives the display data output by the timing controller and provides a corresponding pixel voltage to each of the opened pixel units. The electrophoretic panel is composed of upper and lower substrates, a common electrode, a pixel electrode, and an electrophoretic layer between the upper and lower substrates, wherein the common electrode receives a common voltage; each pixel electrode is connected to a TFT unit to constitute the above a pixel unit; when the TFT unit is turned on by the scanning signal, the pixel electrode 遂 receives the source voltage output from the source driving circuit, and the common voltage of the common electrode forms a voltage across; the electrophoretic layer, in an embodiment, may be plural a microcapsule, wherein each microcapsule contains colored charged particles, such as positively charged black particles and negatively charged white particles, respectively, moving to different positions above and below under the electric field generated by the above-mentioned voltage across the pressure, and finally forming image.

Referring to FIG. 1 , a preferred embodiment of the present invention is disclosed. An output block diagram of the source driver circuit of the swimming display. The source driving circuit mainly provides a plurality of positive voltage switches swp1, swp2, ... swpn, zero voltage switch sw0 and a plurality of negative voltage switches swn1, swpn2, ... swnn at the output end, each positive voltage or negative The voltage on relationship controls the output of a particular voltage; the zero voltage switch sw0 corresponds to a ground voltage. When the timing controller receives the picture data and outputs corresponding data (data) to the source driving circuit, the decoding unit 11 of the source driving circuit cooperates with the control signal (act) to selectively turn on one of the switches to The corresponding positive voltage and negative voltage are output and used as the source voltage (ie, the pixel voltage).

Please refer to FIG. 3 for further reference to a first preferred embodiment of the present invention. A block diagram of a circuit applied to a source driver circuit of an electrophoretic display. Source drive of the invention The dynamic circuit mainly includes a first temporary storage unit (LH1), a second temporary storage unit (LH2), a logic control unit 10, a decoding unit 11, and a switching unit (SW).

Referring also to Figure 4, the letter of the output terminal of the source driver circuit of Figure 3 Waveform. The first temporary storage unit (LH1) may be a latch for receiving a first latch enable signal (le1) for extracting data (data_bus) from the timing controller. And stored as a first write data (data1). The write data from the timing controller is that the timing controller outputs corresponding display data according to the screen data of a display screen.

The second temporary storage unit (LH2) can also be a latch, one input thereof The end is coupled to an output of the first temporary storage unit (LH1). The second temporary storage unit (LH2) is configured to receive a second latch enable signal (le2) for capturing the first write data output by the first temporary storage unit (LH1), and storing the first write data as a first Second, write data (data2).

The two input ends of the logic control unit 10 are respectively coupled to the first temporary storage unit An output end of (LH1) and an output end of the second temporary storage unit (LH2) for receiving the first write data (data1) and the second write data (data2), thereby determining the first Whether a write data (data1) and the second write data (data2) satisfy a predetermined difference value, and output a control signal (act) when the predetermined difference value is satisfied. The first write data (data1) and the second write data (data2) that are input to the logic control unit 10 are compared with each other, and the second write data (data2) is compared to store the previous timing. The first write data; the first write data (data1) being compared is the first write data of the latter sequence, that is, the difference value of the first write data of the preceding and following timings is compared. The logic control unit 10 has another input terminal for receiving an action enable signal (act_en), when the logic control unit 10 compares the first write data (data1) with the second write data (data2). When the predetermined difference value is obtained, the logic control unit 10 outputs the signal according to the action enable signal (act_en). The control signal (act).

The decoding unit 11 is coupled to the second temporary storage unit (LH2) and the logic control Unit 10, the decoding unit 11 directly outputs the second write data (data2), or when receiving the control signal (act) from the logic control unit 10, the second write according to the control signal (act) The input data (data2) is rewritten into a temporary write data (data3).

The switching unit (SW) is coupled to the decoding unit 11 to receive the second write resource Material (data2) or the temporarily written data (data3), which outputs a corresponding source voltage according to the second write data (data2), or outputs a corresponding third voltage according to the temporarily written data (data3) . As shown in Fig. 1, the switching unit (SW) is composed of a plurality of positive voltage switches swp1, swp2, ... swpn, zero voltage switch sw0 and a plurality of negative voltage switches swn1, swpn2, ... swnn. Receiving, according to the second write data (data2) or the temporarily written data (data3) outputted by the decoding unit 11, selectively turning on one of the switches to output a corresponding second write data (data2) or The positive voltage, negative voltage, or ground voltage of the data (data3) is temporarily written.

Please refer to FIGS. 2A-2C for the source driving circuit of the present invention. When switching between different voltage switches, an additional voltage switch switching is further added, that is, the temporary write data (data3) is used to temporarily insert a third voltage instead of the second write data (data2). For example, as shown in FIG. 2A, when the output source voltage is to be switched from the positive voltage vpos1 of the higher level to the positive voltage vpos2 of the lower level, the source driving circuit of the present invention passes the temporarily written data ( Data3) drives the switching unit (SW) to first output a third voltage lower than the level, for example, zero voltage, and then switch to the lower level positive voltage vpos2, thereby reducing the voltage convergence caused by the load effect and avoiding Display error. As shown in FIG. 2B, when the output source voltage is to be switched from a lower level negative voltage vnegx to a higher level positive voltage vpos2, the source driving power of the present invention The circuit system drives the switching unit (SW) to output a higher third voltage, such as a positive voltage vpos1, and then switch to the positive voltage vpos2 through the temporarily written data (data3), so that the voltage on the load can be made. The level is pulled high early to reduce the difference between the required voltage on the load and the expected voltage in a shorter period of time. Further, as shown in FIG. 2C, when the output source voltage is to be switched from the positive voltage vposx to the negative voltage vnegx, the source driving circuit of the present invention drives the switching unit (SW) by the temporarily written data (data3). First, a third voltage of a zero level is output, and then the negative voltage vnegx is switched, whereby the action of first cutting to the zero voltage level is equal to the direct switching from the positive/negative voltage level to the next level. Only the work of zero voltage level to the next voltage level needs to be paid, so the power consumption can be effectively reduced.

In summary, in an embodiment, when the first write data (data1) and the first When the write data (data2) corresponds to different voltage levels of the same polarity and the voltage level corresponding to the write data received by the second write data (data2) is low, the voltage level of the third voltage is lower than The voltage level corresponding to the second write data (data2), wherein the voltage level of the third voltage is preferably zero voltage level.

In an embodiment, when the first write data (data1) and the second write data (data2) corresponding to different voltage levels of the same polarity and the voltage level corresponding to the second write data (data2) is higher, the voltage level of the third voltage is higher than the second write data (data2) ) Corresponding voltage level.

In an embodiment, when the first write data (data1) and the second write data (data2) corresponding to the voltage level of different polarities, the voltage level of the third voltage is a voltage corresponding to the voltage level corresponding to the first write data (data1) and the second write data (data2) Between the positions. The voltage level of the third voltage is preferably zero voltage level.

Further referring to Figures 5 and 6, Figure 5 is a second according to the present invention. A circuit block diagram of a source driving circuit applied to an electrophoretic display of a preferred embodiment; and a signal waveform diagram of an output terminal of the source driving circuit of FIG. 5 is shown in FIG. The difference between this embodiment and the first embodiment is that the third embodiment further includes a third temporary storage unit (LH3) coupled between the logic control unit 10 and the decoding unit 11. As shown in FIG. 5, an input end of the third temporary storage unit (LH3) is coupled to an output end of the logic control unit 10, and an output end of the third temporary storage unit (LH3) is coupled to the decoding. An input of unit 11. The logic control unit 10 determines whether the first write data (data1) and the second write data (data2) satisfy a predetermined difference value, and outputs a first control signal (actx) when the predetermined difference value is satisfied. The third temporary storage unit (LH3) receives the first control signal (actx) according to an action enable signal (act_en), stores the control signal (act), and outputs the control signal (act) to the decoding unit 11.

Further referring to Figures 7 and 8, Figure 7 is a third embodiment in accordance with the present invention. A circuit block diagram of a source driving circuit for an electrophoretic display of a preferred embodiment; and a signal waveform diagram of an output terminal of the source driving circuit of FIG. 7 is shown. The difference between this embodiment and the first embodiment is that a third temporary storage unit (LH3) coupled between the logic control unit 10 and the second temporary storage unit (LH2) is further included. As shown in FIG. 7, an input end of the third temporary storage unit (LH3) is coupled to an output end of the second temporary storage unit (LH2), and an output end of the third temporary storage unit (LH3) is An input of the logic control unit 10 is coupled. The third temporary storage unit (LH3) captures the second write data (data2) output by the second temporary storage unit (LH2) according to the first latch enable signal (le1) to be stored as a third write. Data (data3), and outputting the third write data (data3) to the logic control unit 10; the logic control unit 10 determines the first write data (data1) and the third write data (data3) Whether a predetermined difference value is satisfied, when the predetermined difference value is satisfied, the logic control unit 10 is based on an action enable signal received at the other input end (act_en) outputs the control signal (act) to the decoding unit 11.

Further referring to FIG. 9, the present invention is based on the source driving circuit described above. A source driving method is provided, comprising the following steps: 100: receiving write data, wherein the step of receiving write data is latched by a first temporary storage unit (LH1) and a second temporary storage unit (LH2) The method reads and stores the write data from a timing controller, wherein the write data stored by the first temporary storage unit (LH1) is defined as a first write data (data1); the second temporary storage unit (LH2) The first write data (data1) outputted by the first temporary storage unit (LH1) is stored to be stored as a second write data (data2); 101: the corresponding source voltage is output according to the write data, wherein The second write data (data2) is outputted to a switch unit (SW) by a decoding unit 11 connected to the second temporary storage unit (LH2), and the switch unit (SW) is further based on the second write data. (data2) output corresponding source voltage; 102: comparing, by the logic control unit 10, whether the write data received in the previous timing and the write data received in the subsequent timing satisfy a predetermined difference value, wherein the logic control unit 10 The second write data (data2) and the first temporary storage unit (LH1) are next The first write data (data1) stored in the sequence is compared; 103: when a predetermined difference value is received between the write data received by the current post-timing, a control signal is output, wherein the logic control unit 10 is enabled according to a control The signal (act_en) outputs a control signal (act) to the decoding unit 11; 104: outputs a corresponding third voltage according to the control signal, instead of the source voltage corresponding to the output corresponding to the written data received according to the previous timing, The decoding unit 11 rewrites the second write data (data2) into a temporarily written data according to the control signal (act). (data3), the switch unit (SW) outputs a corresponding third voltage according to the temporarily written data (data3); wherein, in an embodiment, the write data received by the current post-timing corresponds to different voltages of the same polarity When the bit level corresponding to the write data received by the previous timing is lower, the voltage level of the third voltage is lower than the voltage level corresponding to the written data received by the previous timing, and the third voltage is The voltage level is preferably zero voltage level; or, when the current data received by the subsequent timing corresponds to different voltage levels of the same polarity and the voltage level corresponding to the written data received by the previous timing is higher, the third The voltage level of the voltage is higher than the voltage level corresponding to the written data received by the previous timing; or, when the current data received by the subsequent timing corresponds to the voltage level of different polarity, the voltage level of the third voltage Between the voltage level corresponding to the currently written data and the voltage level corresponding to the previous written data, wherein the voltage level of the third voltage is preferably zero voltage level; and 105: ending the control signal And according to the latter The received write data outputs a corresponding source voltage, wherein the temporary write data (data3) is restored to the second write data (data2) of the next timing by resetting the control signal (act), by the switch The unit (SW) outputs a corresponding source voltage according to the second write data (data2), completes the switching operation of different source voltages, and continues to receive the next written data, that is, returns to the foregoing step 100.

In summary, the present invention mainly compares before and after writing through a logic control unit. The difference in data is to temporarily insert a third voltage when the source voltage is switched between two different voltage levels. Compared with directly switching the source voltage from the current level to the next level, the present invention temporarily inserts the third voltage to reduce the known non-ideal effect or power consumption, so that the electrophoretic display achieves better display effect. And can extend its service life.

Although the present invention has been disclosed in the preferred embodiments, it is not intended to limit the present invention. Anyone who is familiar with the art may do so without departing from the spirit and scope of the present invention. Various changes and modifications are intended to be included within the scope of the appended claims.

LH1‧‧‧ temporary storage unit

LH2‧‧‧ temporary storage unit

10‧‧‧Logical Control Unit

11‧‧‧Decoding unit

SW‧‧‧Switch unit

Claims (15)

A source driving method for an electrophoretic display, comprising the steps of: receiving a written data; outputting a corresponding source voltage according to the written data; comparing the written data received by the previous timing with the logic receiving unit and receiving the subsequent timing Whether the written data satisfies a predetermined difference value; when the predetermined difference value is received between the currently received timing data, a control signal is output; and a corresponding third voltage is output according to the control signal, instead of the previous timing The source voltage of the output corresponding to the received write data; and the corresponding source voltage of the write data output that ends the control signal and is received according to the latter timing. The source driving method for an electrophoretic display according to claim 1, wherein the step of receiving the data is latched and stored by a first temporary storage unit and a second temporary storage unit. Write data from a timing controller, wherein the write data stored by the first temporary storage unit is defined as a first write data; and the second temporary storage unit captures a previous time output of the first temporary storage unit The first write data of the sequence is stored as a second write data, and the second write data is used for comparison with the first write data stored by the first temporary storage unit at the next timing. The source driving method applied to the electrophoretic display according to the first aspect of the patent application, wherein the written data received by the current post-timing corresponds to different voltages of the same polarity When the voltage level corresponding to the write data received by the subsequent timing is low, the voltage level of the third voltage is lower than the voltage level corresponding to the write data received by the latter timing. The source driving method applied to an electrophoretic display according to claim 3, wherein the voltage level of the third voltage is zero voltage level. The source driving method applied to the electrophoretic display according to the first aspect of the patent application, wherein the write data received by the current post-timing corresponds to different voltage levels corresponding to the same polarity voltage level and the write data received by the subsequent timing When the value is higher, the voltage level of the third voltage is higher than the voltage level corresponding to the written data received by the latter timing. The source driving method applied to the electrophoretic display according to the first aspect of the patent application, wherein when the current data received by the subsequent timing corresponds to the voltage level of different polarities, the voltage level of the third voltage is later than The voltage level corresponding to the received data received by the sequence is between the voltage level corresponding to the previous written data. The source driving method applied to an electrophoretic display according to claim 6, wherein the voltage level of the third voltage is zero voltage level. A source driving circuit for an electrophoretic display, comprising: a first temporary storage unit configured to receive a first latch enable signal to capture a write data and store the first write data; a second temporary storage unit for receiving a second latch enable signal for capturing the first write data and storing the second write data; and a logic control unit coupled to the first temporary data a storage unit and the second temporary storage unit, It is configured to determine whether the first write data and the second write data satisfy a predetermined difference value, and output a control signal when the predetermined difference value is satisfied; a decoding unit is coupled to the second temporary storage unit And the logic control unit, the decoding unit directly outputs the second write data, or when receiving the control signal from the logic control unit, rewriting the second write data into a temporary write data according to the control signal And a switching unit coupled to the decoding unit to receive the second write data or the temporarily written data, and output a corresponding source voltage according to the second write data, or according to the temporarily written data A corresponding third voltage is output. The source driver circuit of the electrophoretic display device of claim 8, further comprising a third temporary storage unit coupled between the logic control unit and the decoding unit, wherein the third temporary storage unit is When receiving a third latch enable signal, the control signal output by the logic control unit is captured and stored, and output to the decoding unit. The source driving circuit for an electrophoretic display according to the eighth aspect of the invention, further comprising a third temporary storage unit coupled between the logic control unit and the second temporary storage unit, the third temporary The storage unit captures the second write data output by the second temporary storage unit according to the first latch enable signal, stores the third write data, and outputs the third write data to the logic control unit. The logic control unit determines whether a predetermined difference value is satisfied between the first written data and the third written data, and outputs the foregoing control signal when the predetermined difference value is satisfied. The source driving power applied to the electrophoretic display as described in claim 8 a circuit, wherein when the first write data and the second write data correspond to different voltage levels of the same polarity and the voltage level corresponding to the write data received by the second write data is lower, the third voltage The voltage level is lower than the voltage level corresponding to the second write data. The source driving circuit applied to the electrophoretic display according to claim 11, wherein the voltage level of the third voltage is zero voltage level. The source driving circuit applied to the electrophoretic display according to the eighth aspect of the invention, wherein the first write data and the second write data correspond to different voltage levels of the same polarity and the second write data corresponds to When the voltage level is higher, the voltage level of the third voltage is higher than the voltage level corresponding to the second write data. The source driving circuit of the electrophoretic display, as described in claim 8, wherein when the first write data and the second write data correspond to voltage levels of different polarities, the voltage of the third voltage is The bit position is between a voltage level corresponding to the first write data and a voltage level corresponding to the second write data. The source driving circuit applied to the electrophoretic display according to claim 14, wherein the voltage level of the third voltage is zero voltage level.