E-paper Display -- FAQ
- Time of issue:2020-05-18 15:40
E-paper Display -- FAQ
- Time of issue:2020-05-18 15:40
We have compiled all the collected e-paper FAQs into a small tool that allows customers to easily find out the answers themselves. If you have a need, please click here to view.
Q: Are your E-Paper Displays RoHS compliant?
A: All of Good Display E-Paper Displays are RoHS compliant.
Q: What is the difference between an Matrix display and an Segmented display?
A: The underlying ePaper technology is very similar but is tuned to the needs of the different applications of a Matrix display versus a Segmented display.
Matrix displays are intended for applications requiring the display of many different forms of text and images. These displays comprise of a large array of pixels. These individual pixels are controlled by a TFT array similar to what you will have a typical computer monitor or TV screen.
Segmented displays are intended for applications where the display requirements can be met using predefined segments that can be turned on or off. This is similar to what one would see in a typical calculator with a numeric or alphanumeric display.
Basically will the display be made up of an array of pixels or by a collection of predefined shapes.
Q: What is Good Display's minimum purchase quantity for Matrix e-paper displays? And what about the small size, for example, 2.9 inch?
A: You can purchase one unit matrix display for standard products, but you must have 100,000 unit and even more volume for custom products, this varies based on the size and requirements of the display application and whether it is a custom or standard size display. It is best to discuss your requirements with a member of our sales team. And for the small size(less than 3.5 inches), the molding fee is about 100,000 US dollars, the MOQ is 500K.
Q: What is the pricing for Good Display Matrix E-ink displays?
A: Pricing for Matrix displays depends on volumes and whether the display is a custom or standard display. The main driver of pricing is the overall display size, whether the display is monochrome or color.
And you can get the current pricing for Matrix E-ink displays from the following linking.
Q: How large/small can Matrix e-ink displays be?
A: The size and shape of a Matrix e-ink display is totally dictated by the size of the electrical backplane that the FPL is laminated to. Displays can be very small or very large. E Ink has standard display modules. Almost any size and shape can be made depending on the volumes.
Q: What voltage is required to drive a Matrix e-ink display?
A: The drive for E Ink displays is typically 15 volts. An ecosystem of electronic components exists for design of complete epaper systems.
Q: How much power does a Matrix e-ink display consume?
A: Matrix e-ink displays are bi-stable. This means that they only consume power while the display is being updated. No power is required to maintain an image after it has been updated. The power required to for the update process depends on the size of the display but is of the order of microwatts.
Q: Does Good Display have developer kits for Matrix products?
A: Yes there are E-ink display development kits available for Matrix products from Good Display. and you can buy these development kits online or contact our sales.
Q: Does Good Display have a color product or is it only monochrome?
Q: How long does it take to update an image on an Matrix e-ink display?
A: An e-ink display module supports numerous modes for updating the display. Different modes exist to support the different update requirements. Update times can be as short as 300 msec. for the entire display. Also to consider is that because e-ink screens are bi-stable, only the regions of the screen that are changing require updating. Any pixels that are not changing do not require updating.
Q: Can an Matrix e-ink display support animation or video rates?
A: Using the faster update modes, e-ink screens can support animation quality video rates. A number of examples are available from customers that show examples of e-ink screens showing video.
Q: Does Good Display provide or support flexible matrix displays?
A: The flexibility of an EPD display is controlled by the backplane. Good Display does support flexible backplanes, if you're intrested, please contact us.
Q: What is the thickness of an Matrix E-Paper display?
A: Thicknesses range from 1mm to 1.2 mm. This includes the FPL, protective sheet and the glass TFT backplane.
Q: What is the temperature range for Matrix E-Paper displays?
A: The operating temperature range for a Matrix e-ink display is from 0°C-50 °C, and the storage temperature range is from -20°C-70°C.
The operating temperature range for a Matrix DES display is from -20°C-60 °C, and the storage temperature range is from -25°C-70°C.
Q: What is waveform?
A: Waveform are predefined voltage impulse sequences used by display controller to manipulate ink.
The voltage sequence and temperature range are stored in a lookup Table(LUT) and is precisely paired to the display by production lots to enable precise placement of pigment to achieve accurate gray-level.
Q: Why does waveform need?
A: Because of every lots of E INK material has slightly different at ink characteristics which effects are temperature dependent.
So, waveform is a driving method which consider the factor of temperature, production lot, display size and waveform type to control the each lots of EPD performance at same range, and this is Good Display's responsibility to provide the suitable waveform to our customer.
Q: What are the types of waveform mode?
A: The waveform mode optional argument allows you to select the type of waveform update.
The INIT waveform flashes the display and drives the display to a white state. Used this waveform if the display is in an unknown state such as when the previous image is unknown due to reboot, or just test the host function.
Direct update is only used when pixels are updating from any gray-level to either white to black such as handwriting or menu. Gray pixels will not be affected, MU/DU is about twice as fast as GC or GU.
Grayscale Update is a non-flashing waveform that can be used to update changing grayscale pixels.
Grayscale Clear is a flashing waveform used to provide the accurate update performance. All pixels are updated or cleared.
Q: What is the normal product lifetime of Good Display's e-ink display?
A: For standard products, it is a minimum of 5 years or the times of refresh is 1,000,000.
Q: Do Good Display E-Paper Displays have CE certification?
A: CE certification is typically given to end products. Since the E-Paper Display is a component, it does not carry CE certification.
Q:Can it be realistic? If want to integrate the circuit onto the e paper FPC to replace PCB directly, the PCB will not be used in the product, and the FPC of the epaper need open a mould
A: If the FPC fixed with the components will have a yield problem. The FPC is bendable and it is easy to cause the loss of the components. This solution cannot be operated.
Q:Can you do an irregular shape segmen E paper?
A:Yes,, we can .As long as the number of segment is not too many and IC is easy to choose. Additionally, PCB is more easy packaging than that of flexible one . But we can do if must be, tooling cost will be higher 20% - 30% than normal type segment E paper .
Q: Can large size monochrome or color E paper support FPC open mould?
A:Yes. Minimum order is 10K.The sample delivery date is 25 to 30 days after payment of the model fee.
Q: What does LUT and OTP stand for?
A:LUT stands for external waveform, OTP represents the built-in waveform.
Q: How to set LUT for OTP support products?
A: The partial refresh support product needs LUT, and the rest can be.
Q: Partial refresh remnant shadow problem for GDEW0154D27
A: Extend the refresh time, add a full update after several times.
Q: What is the voltage of adapt board?
A: 3.3 V, 5 V without any connection.
Q: The reason for the horizontal bar in the three color electronic paper.
A: There is a possibility of a horizontal bar for hardware settings and improper changes in software programs.
Q: The cause of red diffusion in the short time after the refresh of the color electronic paper.
A: When the steady state is not established, the refresh is stopped.
Q: Why is a SPI Epaper screen longer than a parallel screen when updating?
A: SPI interfaced EPDs have only one data bus while the Parallel interfaced ones have 8-16, due to which within the same time duration, the SPI interfaced EPDs can transmit one digit data while the other can transmit 8-16 digits.
Q: Storage humidity for electronic paper.
A: 40% to 70%.
Q: Is the E paper display can work on Operation Conditions: Temperature 0℃~40 ℃ ; Humidity 5%~90% RH ?
A: The operating Temperature is okay, but we recommend the suitable Humidity is from 35% to 65% RH.
Q: If it is acceptable for Indoor Humidity about 30-60% in Summer & 30-80% in Winter?
A: The Humidity in Summer and in Winter can be acceptable for the matched Temperature range of 0--25℃or +10--35℃.
Q: If Tcon demo can come with temperature sensor?
A: The IC LM75A installed on the Tcon is temperature sensor.
Q: How to solve the unclean problem when 2.9 inch e-paper display refreshed in the first time from deep sleep mode?
A: The process of refreshing from deep sleep mode is the proccess of re-energizing actually. So it is necessary to have a full refresh first to avoid ghost.
Q: Can our normal temperature e-paper display be used under strong light? Why is it partially darkened under strong light?
A: Under such circumstance the particle will become visible because the light dry them out and rid them of activity, from which the harm caused is irreversible.We recommend customers to do outdoor anti-light treatment for EPD.
Q:What is the refreshing time of e-paper display?
A:1,For 2-color(black and white) e-paper display, full refresh is generally around 6s. The display with partial refresh, full refresh： 1s；partial refresh ： 300ms around.
2, For 3-color(black, white and red/yellow) e-paper display, full refresh is generally around 12s except for GDEW0154C39 and GDEW0213C38, both of them are 25s around.
Q: Can the demo board integrate with the Arduino system?
A: No, only the Raspberry Pi system.
Q: If the waveform file does not correspond to the display, will it affect the refresh?
A: Wave files and e-paper must be one-to-one correspondence. If confused, it may affect the refresh.
Q: How to intuitively distinguish the full refresh and the partial refresh?
A: The picture does not flash when partial refresh.
Q: What is the meaning of the DSP in the e-paper timing diagram?
A: The DSP is the feedback information that the e-paper passes to the MCU. After receiving the information, the MCU indicates that the e-paper data transmission is completed. This command is generally not used.
Q: Can I use the emulator to power e-paper directly?
A: No. Because the power supply of the emulator is unstable, the voltage will be pulled down when the e-paper is refreshed, and eventually it will not work properly.
Q: How does the e-paper rotate 180 degrees?
A: This can usually be done by modifying the initial scan direction.
Q: I can't find the 0x11 and 0x13 commands in the e-paper specification. What should I do?
A: If the required command is not found in the specification, the customer can consult the IC manual, which has detailed command explanations.
1. After downloading the program of the e-paper, you need to remove the short cap of P12, otherwise the e-paper display will not be lit.
2. In the case of long-term non-refresh, we need to power off the electronic paper or put it into deep sleep mode, otherwise it will damage the IC.
Q:When there is a delay in the middle of the two pictures when the e-paper is refreshed, can it be removed?
A:Yes, it can be removed. Since the delay is realized by the check-busy function and the delay in example code is for more time to observe the refresh.
Q:Does Good Display's DEMO board support the GCC compilation environment?
A:This does not support, the DESPI board is the Keil development environment, and the Arduino board is the Arduino development environment.
Q:What is the capacitance range of the e-paper drive circuit?
A:In theory, 50V is needed, and the user can also use 25V instead of the actual design.
Q:Precautions for fixing the IC of flexible e-paper
A:When installing the flexible electronic paper, make sure that the IC part is not bent to avoid tearing the IC sealant and causing IC failure.
Q:After refreshing the e-paper display fastly, there is an afterimage on the screen. Why?
A:Fast refresh is more similar to partial refresh. Customers need to follow the operation requirements of partial refresh. After refreshing 5 times, please use slow refresh to clear the screen once.
Q:What if I want to update the display content in different locations at the same time?
A:When partially refreshing, a new buffer needs to be created in the microcontroller to store the display content that needs to be updated. When updating the display screen, this part of the cache content can be updated at the same time.
Q:The screen appears garbled and the display area becomes smaller when the e-paper display is refreshed for the second time. What is the reason?
A:When the display is refreshed for the second time, it needs to be re-initialized, otherwise the resolution is not locked, which will cause the display area to be unstable or display garbled characters.
Q:The screen sometimes fails to start. What is the reason?
A:The reset time of the electronic paper is short, and the reset fails, which is easy to cause the failure to start.
Q:What is the reason for the burning of large-size e-paper display?
A:Large-size e-paper peripheral drive circuit filter capacitors are generally relatively large, such as GDEW075T7, which is 10uF. If it is too small, it will cause the e-paper displa to discharge incompletely and cause damage to the diaphragm.
Q:Can GDEW1248T3 be directly driven by Raspberry Pi?
A:This e-paper display can support Raspberry Pi driver. When using it, users need to use the Raspberry Pi adapter board and 12.48-inch driver board, which can be directly plugged in.
Q:Can GDE060BA be driven by Raspberry Pi?
A:Raspberry Pi can drive parallel e-paper. This e-paper display mainly has the problem of insufficient IO, which can be achieved by expanding the IO port.
Q:How does GDE060F3 determine the origin coordinate position?
A:The origin coordinate of this e-paper is in the upper left corner of the screen (the e-paper IC is placed horizontally and the FPC is facing down).
Q:For UC series e-paper dispay, some single-chip microcomputers are stuck in BUSY and cannot run down. How to solve?
A:You can cancel the 0x71 command in the busy function. This operation does not affect the function judgment of the BUSY pin.
Q:How to set the direction of e-paper under 3.71 inches?
A:For small size e-paper under 3.71 inches, the general way to fetch it is vertical scanning. If you want to change to horizontal scanning, the corresponding electronic paper initialization also needs to be modified simultaneously.
Q:Calculation method of maximum power of e-paper
A:Maximum power = rated voltage x peak current
Q:The calculation method of e-paper's DPI
A:Number of 1 inch pixels, for example: 1.54 inch resolution 152*152, AA area 27.5x27.5, DPI=152/(27.5/25.39)=140
Q: The peripheral part of GDEW0102I4F turned black
A: It is likely that the ambient humidity is too high that it affects EPD's film to work normally. Therefore, we suggest an airproof storage if the EPD's not being used and so as well the terminal products that should be sealed well to prevent such harm
Q: Does EPD supports hardware SPI?
A: The SPI interface of EPD supports hardware SPI but the MISO of the mother board should be idle when connecting.
Q: The length of FPC cable of e-paper display demo kit.
A: We do not recommend it to be over 20cm since a long FPC cable may easily result in error in data transmission.
Q: Does DEArduino support GUI program?
A: Since the RAM of the mother board is only 2k, it is not suitable for a complete GUI interface.
Q: What are the functions of these two PINs, TSCL and TSDA regarding the temperature sensor?
A: These two PINs connect the outer temp. Sensor to read the environment temperature since there was no inner temp. sensor in EPDs in early stage.
Things are different nowadays since most of EPDs have the inner temp. sensor and due to that the outer interface gradually becomes outdated.
Q: What may result in a bad partial refresh? And sometimes the background color still gets too deep even after a full screen clean. How may I solve it?
A: There are several factors that may result in a bad partial refresh:
1. Time inconsistency in partial refresh driver with the waveform
2. Ghost shadows remain because you forget extra full refresh after the fifth partial refresh as we suggest
3. Please also do not forget to delay longer the interval between updates to reduce ghost shadows.
Q: Will I need an extra boost IC if I go for a 3V power supply for my EPD?
A: If your EPD is parallel interfaced, like 4.3, 6, 9.7 and 13.3inch, where you need an external Tcon chip and to do so you have to boost the voltage from 3V to 5V (power supply for boost chip TPS65185); if it is SPI interfaced, you do not have to since the boost is realized internally and you need only to follow the circuit in datasheet to finish the peripheral devices.
Q: What is the IC voltage for commonly used graphic dot-matrix EPDs?
|1.02'', 1.54'', 2.13'', 2.6'', 2.7'', 2.9'', 3.71'', 4.2'', 5.83'', 7.5'' EPDs||2.4V||3.3V||3.7V|
|4.3'', 6'', 7.8'', 8'' EPDs||3.0V||3.3V||3.6V|
Q: Which part is for TCON waveform storage of AVT6203?
A: The FLASH for it can be divided into two parts:
1. 0X0~0X885 command code （initial TCON code including frequency, resolution and etc）
2. After 0X886 is the part which is for waveform to drive EPD. Therefore, you have to start after 0X886 for waveform.
Q: Can PIC24 series MCU drive EPDs?
A: Yes, but only for the SPI interfaced EPDs.
Q: Why are there strips on a tri-color EPD?
A: Any inappropriate revision in hardware or software settings can result in the situation. If none of them exists and strips remain even after multiple times of refreshing, you may come across a broken EPD panel or an ill-connected IC.
Q: Any special requirements for the ambience when driving the EPD?
A: First you have to avoid direct UV light against the EPD; and you must follow the temperature range to operate it;
In addition, for rarely used tri-color EPDs, you have to full white the screen and put them face-down to well store them.
Q: How can I further lower the power consumption of EPD?
A: Switch off the driving circuit and IC circuit after EPD entered deep sleep mode, where the power eaten can be zero.
Q: Can I just simply use EPD model A’s example to drive another EPD model B?
A: Technically we do not recommend doing so although under most circumstances it’s doable as long as the IC and resolution of the two models are identical.
Q: Can EPDs support External FLASH?
A: Currently only the 5.83(600*448) and 7.5(640*384) EPDs have the FLASH element since present example codes we made have not considered using it. Users with the need can refer to the details in SPI interface in datasheet.
Q: Which MOS should I choose?
A: We recommend Si1304BDL or Si1308EDL SOT-23(SC70) but if they are hard to secure you can opt for AO3400 or refer to the datasheet for a matched one. Besides the A03400 mentioned before, 2N7002 can also be a good choice.
Q: Which diode shoud I choose?
A: Users can refer to the components’ parameters to select one such as MBR0530 30V 0.5A, or refer to the datasheet for a high-frequency diode with the same performance.
Q: What may result in a powerful EPD working current?
A: First you need to check whether the software has been transplanted correctly; if normal, then check the hardware circuit to see if there is a short circuit or false soldering.
Q: Regarding EPD SIP communication
A: If users opt for the MCU built-in SPI interface, where the SDIN interface is two-way IO interface and it uses simulated SPI interface to drive the EPD. They need to block the built-in SPI interface and use a normal IO as the SPI interface. Users can try driving the EPD via MCU built-in SPI if the IO communication is normal.
Q: What to do when PIN BUSY is always at busy state.
A: It’s likely that the SPI serial port communication fails so that the IC does not work at all.
Q: GDEW0154M09 has heavy ghost shadows after several times of fast refresh.
A: It can be improved by adding 0x30 in initialization, data part writing 0x3F to lower PLL update frequency.
Q: How many ways of updating for EPDs?
A: There are usually full refresh (B/W, 4 grayscale and 16 grayscale), partial refresh(only part of the screen updates without screen splashing) and partially full refresh(only part of the screen full refreshes)
Q: Consumption for stand-by mode and sleep mode
A: Normally, below 20uA for stand-by mode and below 5uA for sleep mode.
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