1. Visual Inspection: Please check if the e-paper FPC is reversed, if the adapter board FPC socket is manually damaged, if the FPC socket and electronic components have cold solder joints, and if the e-paper FPC is torn. If using our development board, check if the P3 jumper cap on the main board is connected and if the RESE DIP switch on the adapter board is selected correctly.
2. Hardware Inspection: Check if the driver circuit design is correct, measure the voltages of PREVGH and PREVGL to see if the boost is successful. If the boost fails, check if the boost part of the driver schematic is correct, if the components meet the requirements (ensure the boost capacitor has sufficient voltage resistance; insufficient voltage resistance will cause the capacitor to burn out during boosting), and if the soldering is normal. The MOS tube is the most likely component to have issues.
3. Software Inspection: If the boost is normal, check the software part - is the driver program correct, are the pin definitions correct? You can test the SCL and SDA signals of the driver board and confirm their correctness by comparing with the SPI waveform in the specification sheet.

Avoid direct sunlight. Under strong light, the display particles of e-paper (charged particles in microcapsules) will dry out under strong light irradiation, lose activity and fail to refresh. This situation is irreversible. At the same time, good moisture and waterproof measures should be taken, and operation should be strictly in accordance with the temperature and humidity range required by the specification sheet. When the e-paper is not in use for a long time, it should be placed upside down with the screen displaying a full white image.

The display grayscale of electrophoretic e-paper is determined by the spatial position of particles in microcapsules or microcups. Black particles and white particles undergo electrophoresis under the action of voltage. The voltage timing that causes particles to undergo electrophoresis is the driving waveform of e-paper. The driving waveform is the core part of the e-paper display, and optimizing the driving waveform will directly affect the display effect of the display. The driving waveform file is a parameter used to illustrate the voltage timing that causes particles to undergo electrophoresis, and needs to be called regularly when the e-paper is refreshed. Due to differences in materials and manufacturing processes of electrophoretic matrices of different batches of e-paper films, the voltage values required for driving display will be different. What is reflected in the relationship between grayscale, voltage and temperature is the waveform of the e-ink display. Generally speaking, after each batch of electrophoretic matrices is produced, there will be a corresponding waveform file in the form of .wbf file. The film manufacturer provides the waveform file and electrophoretic matrix to the manufacturer of e-paper displays, and then the manufacturer of e-paper displays integrates the protection board, substrate and driver before providing them to customers; if the waveform file does not correspond to the screen, it may cause failure to display or unsatisfactory display effect. For e-ink displays/e-paper displays produced by Dalian Good Display Electronics Co., Ltd., the waveform files have been built into the driver IC of most e-paper displays through OTP (please confirm with the sales engineer when purchasing), so users do not have to worry about this. Of course, customers can also drive the e-ink display by calling external waveform files.

Insufficient or unstable power supply will lead to data loss and thus image offset. It is recommended not to use emulator for power supply.

Incorrect dot matrix generation method will cause screen corruption. If it is partial screen corruption, it is caused by abnormal picture size or dot matrix resolution of the user's image.

In the peripheral driver circuit, cold solder joints of individual capacitors may weaken the driving capability of e-paper and cause abnormal display.

When the e-paper is not refreshed for a long time, it should be powered off or enter deep sleep mode.

There is no delay between e-paper initialization and display. A long delay will cause the e-paper to be in the boosting process for a long time, which may easily damage the e-paper.

Relevant markings are available in the specification sheet. The origin of most e-papers is at the upper right corner, with the vertical direction as the X-axis and the horizontal direction as the Y-axis, except for a few e-papers.

All our e-papers support 90-degree image rotation, which needs to be achieved by changing the dot matrix image and dot matrix generation method. Some e-papers also support 180-degree image rotation, which needs to be achieved through program initialization settings. The specification sheet contains relevant setting instructions for display direction.

In fact, this is the process of eliminating ghosting during e-paper refresh, which is a normal phenomenon. Please pay attention to the final refreshed picture. Full refresh of e-paper requires screen flickering to remove ghosting from the previous picture, while partial refresh has no screen flickering.

Serial SPI e-paper screen has only 1 data line, while parallel e-paper screen generally has 8~16 data lines. Within the same time, serial screen can only transmit 1 bit of data, while parallel screen can transmit 8~16 bits of data simultaneously.

E-paper has a built-in temperature sensor. When the ambient temperature is low, the internally retrieved waveform will be different, and the refresh time will also be affected. If no image is displayed in low temperature environment, the delay needs to be increased to solve the problem.

The sample programs we provide now already use the maximum refresh speed limit of e-paper IC. Shortening the refresh time may cause heavier ghosting, so it is not recommended for users to shorten the time.

2bit input does not mean 2-level grayscale. 2bit input refers to positive voltage, negative voltage, 0 level, and high impedance state, not grayscale. Grayscale is reflected in the waveform.

Number of pixels per inch. For example: 1.54-inch with resolution 152*152, AA area 27.5x27.5mm, DPI=152/(27.5/25.39)=140

After the e-paper enters deep sleep, turn off the power supply of the e-paper driver circuit and IC, which can achieve zero power consumption of the e-paper.

High current in deep sleep mode may be caused by oversized capacitors in the boost part.

These two types of e-papers have exactly the same appearance and structure, the only difference is the IC. The suffix D represents UC8151D, which is an upgraded version of UC8151C. Compared with the old version, this IC has stronger driving capability and the refresh speed of e-paper is further improved.

When the three-color e-paper is not in use for a long time, it needs to be displayed with full white and stored in strict accordance with the product use and storage precautions in the specification sheet.

Red turning black is generally caused by the following situations: 1. Failure of peripheral boost circuit, insufficient boosting. 2. FPC tearing at VCOM pin. 3. Poor batch quality of the film itself, resulting in red turning black.

Theoretically, it can be used as monochrome e-paper. However, when used in this way, the corresponding monochrome program needs to be used to refresh the three-color e-paper. If there is no corresponding monochrome program, it needs to be achieved by loading external waveform files.

The IC of flexible e-paper is not allowed to be bent, and the display area is not allowed to be repeatedly bent. In addition, the so-called flexibility means that the substrate is relatively soft and the material is thinner and lighter. It is recommended that users do not place hard objects under the e-paper during use to avoid damage to the substrate circuit, resulting in stripe flicker on the screen during e-paper refresh.

After the e-paper is refreshed, it needs to be set to sleep mode, or powered off after setting to sleep mode. The refresh interval of SPI serial e-paper should be at least 180s, especially for large-size e-papers. Too short interval will cause ghosting and affect the display effect of e-paper.

LUT is the abbreviation of LOOK UP TABLE, and OTP is the abbreviation of ONE TIME PROGRAMMABLE. LUT essentially means loading waveform files, and waveform files are divided into OTP and REGISTER types, among which OTP is built-in waveform storage mode, and REGISTER is external waveform storage mode. However, there is a disadvantage in achieving partial refresh display effect by calling external waveform files: when the driver IC of the e-paper display is upgraded, the waveform file is also different because the IC is replaced. Customers need to modify the program when using the upgraded display, which brings a lot of inconvenience to customers to a certain extent. This problem does not exist with OTP. In future product production, Good Display will directly build the partial refresh function into OTP to facilitate users' use.

Dalian Good Display has launched several graphic dot matrix e-papers that can achieve partial refresh function. Currently, there are 1.02, 2.13, 2.9-inch flexible e-ink displays, 1.54-inch, 2.13-inch, 2.6-inch, 2.7-inch, 2.9-inch, 4.2-inch e-ink displays. Whether partial refresh can be achieved mainly depends on whether the film FPL used in the e-ink display supports it.

The partial refresh method of GDEW e-paper is: first refresh old data, then refresh new data, and finally update the data. GDEH series e-papers need to refresh the background first before partial refresh.

To reduce ghosting, we recommend that after 5 partial refreshes, a full black and white screen refresh should be added to increase the refresh time interval.

Partial refresh takes 8 pixels as the minimum unit in the x-axis direction. The minimum partial refresh area that e-paper can display is 8 pixels. If it is too small, the e-paper cannot display normally.

To perform partial refresh at different positions simultaneously, unified operation is required in software design: first refresh the data of different positions into the e-paper IC, and finally perform Updata uniformly.

Fast refresh is more similar to partial refresh. Customers need to follow the operation requirements of partial refresh when using it, and clear the screen with slow refresh once after 5 refreshes.

Generally, the partial refresh function has the best effect at room temperature (above 20 degrees). Below 20 degrees, the partial refresh time needs to be increased to offset the ghosting at low temperature. In addition, partial refresh is not supported below 0 degrees.

The waveform files of early three-color e-papers were external, and VCOM could be adjusted through initialization. Now the waveform files of three-color e-papers are all built-in, and VCOM cannot be changed through initialization.

UC series uses Jinghong chips, and SSD series uses Solomon chips. These two types of ICs have similar driving processes for e-paper, but the driving codes are completely different, and the BUSY signal feedback is also opposite.

Fast refresh is also a type of full refresh. Fast refresh has one screen reverse black during refresh, while full refresh requires multiple reverse blacks. Fast refresh generally takes about 2 seconds.

Generally, during partial refresh, first transmit the data part to be displayed, then execute a refresh command uniformly.

The displayed picture is lighter than normal black, that is, grayish, which is generally due to insufficient boosting of the driver circuit, resulting in black particles not being fully displayed, giving the human eye a gray display effect.

It is recommended that customers use GUI programs, which support 0~270 degree display rotation, making it convenient for customers to achieve the desired display screen.

Poor film batch quality, too low ambient temperature, and improper matching of film, IC and glass substrate may lead to poor partial refresh effect of this product.

Generally, the corresponding dot and line exceeding requirements are available at the end of the supporting specification sheet of e-paper.

Official website homepage: www.good-display.com, please enter the product model to search in the upper right corner of the page. The model can be found in the product title or consulted with customer service.New Here? Start Here!_E-Ink Screen - Good Display (Click to view more information)

After the MCU sends a boost command, the e-paper GDR pin sends a switch signal to the peripheral Si1308EDL, and at the same time, Si1308EDL switches continuously to generate high voltage.