USB LCD Displays
244x68 Graphic LCD Display
Part Number: CFA835-TFK
The CFA835 family of modules are intelligent graphic LCDs. They offer an outstanding package: a display, six-button keypad, GPIOs, LEDs, multiple interface choices and memory in an attractive stainless-steel bezel. This powerful module is a great choice for a front panel or user interface display. Between the graphic display and four status LEDs, messages can be quickly and clearly communicated, and the fully decoded keypad allows for clear and robust inputs from the user.
The CFA835 has versatile and reliable packet-based communications with a set of 61 commands that simplify programming. The commands include tools to draw lines, rectangles, and circles. This means putting graphs, tables, and charts on your display is simple. For example, create a chart to display temperature fluctuations over time.
The entire USB LCD module only needs a single power supply. The buck-boost switching supply means the module can operate on a wide power supply voltage range from +3.3v to +5.0v, making it perfect for embedded systems.
This module was made for the demands of a commercial environment. Its wide operating temperature range means this module keeps going in temperatures between -20°C and +70°C.
The fully decoded 6-button keypad allows any combination of key presses to be valid and unique. The keypad is backlit and the large translucent silicone keys are responsive. Plus, a physical keypad reduces the chance of accidental incorrect touches.
The LCD backlight and contrast are adjustable. Both are fully voltage regulated over the power supply range. The LCD backlight comprises 12 LEDs edge lighting the LCD. The keypad LEDs are separately controllable.
The display on this module has a light background with dark blue font.
CFA835-TFK Features
Not sure which LCD module to choose? Compare all of our intelligent display modules.
The CFA835 has versatile and reliable packet-based communications with a set of 61 commands that simplify programming. The commands include tools to draw lines, rectangles, and circles. This means putting graphs, tables, and charts on your display is simple. For example, create a chart to display temperature fluctuations over time.
The entire USB LCD module only needs a single power supply. The buck-boost switching supply means the module can operate on a wide power supply voltage range from +3.3v to +5.0v, making it perfect for embedded systems.
This module was made for the demands of a commercial environment. Its wide operating temperature range means this module keeps going in temperatures between -20°C and +70°C.
The fully decoded 6-button keypad allows any combination of key presses to be valid and unique. The keypad is backlit and the large translucent silicone keys are responsive. Plus, a physical keypad reduces the chance of accidental incorrect touches.
The LCD backlight and contrast are adjustable. Both are fully voltage regulated over the power supply range. The LCD backlight comprises 12 LEDs edge lighting the LCD. The keypad LEDs are separately controllable.
The display on this module has a light background with dark blue font.
CFA835-TFK Features
- 244 x 68 pixel backlit LCD
- Light background with dark blue font
- Edge-lit backlight with 12 LEDs, 6 per side
- Grayscale graphic LCD controller
- 12 o'clock viewing direction
- 6 button backlit fully decoded keypad
- 4 bi-color (red/green) LEDs
- Separate switching LED brightness controllers for keypad and LCD backlights
- Interfaces: USB 2.0, Logic-level Serial, RS232 Serial, I2C and SPI
- Multiple simultaneous serial/SPI/I2C/CAN interfaces (depending on GPIO use)
- Packet based communication with a 61-command set
- Powerful and adaptable module for embedded systems
- MicroSD card slot
- Thirteen general purpose input/output pins (GPIOs)
- Operating Temperatures: -20 to 70°
- Buck-boost switching supply allows wide supply voltage range (3.3v to 5.0v)
- STMicroelectronics STM32F401 microcontroller
- ARM 32-bit Cortex™-M4 CPU @ 84 MHz
- 256K Flash, 64K RAM
- Run STM32 embedded applications on the CFA835 hardware using our open source firmware as a starting point
- Cables for connecting to a variety of host systems
- ATX power supply control functionality allows the buttons on the CFA835 to replace the "power" and "reset" buttons on host system, simplifying front panel design
- System Cooling Accessory Board (FBSCAB) for controlling fans and reading temperature sensors (up to 256 temperature sensors and 64 fans)
- SLED or drive bay bracket for mounting into a system
Not sure which LCD module to choose? Compare all of our intelligent display modules.
Product Variants
Logic Level Serial / RS232 / USB
I2C / Logic Level Serial / RS232 / SPI / USB
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Datasheet
Compliance Documents
Video Demonstrations
CFA835 VU Meter Emulation Demonstration
CFA835 Graphic LCD emulating a VU meter
Raspberry PI CFA835 Integration Video
Integrate a Raspberry Pi with a CFA835
TECHNICAL SPECS
Physical Characteristics
| Column Dots x Row Dots | 244 x 68 |
| Module Overall | width | height | depth |
|---|---|---|---|
| millimeters | 142 | 38 | 20.8 |
| inches | 5.591 | 1.496 | 0.819 |
| *depth doesn't include Keypad | |||
| Viewing Area | width | height |
|---|---|---|
| millimeters | 83 | 27.5 |
| inches | 3.268 | 1.083 |
| Active Area | width | height |
|---|---|---|
| millimeters | 77.97 | 22.38 |
| inches | 3.070 | 0.881 |
| Character Size | width | height |
|---|---|---|
| millimeters | 3.23 | 4.88 |
| inches | 0.127 | 0.192 |
| Character Pitch | width | height |
|---|---|---|
| millimeters | 3.9 | 5.6 |
| inches | 0.154 | 0.220 |
| Dot Size | width | height |
|---|---|---|
| millimeters | 0.3 | 0.33 |
| inches | 0.012 | 0.013 |
| Dot Pitch | width | height |
|---|---|---|
| millimeters | 0.33 | 0.35 |
| inches | 0.013 | 0.014 |
| Weight | 55g |
| Keystroke Travel | 2.4mm |
| Keypad Depth | 12mm |
Optical Characteristics
| Glass Type/Glass Color | FSTN/Light Gray |
| Polarizer | Transflective |
| View Direction | 12 o'clock |
| Sunlight Readable | Yes |
| Backlight Color | White |
| Backlight Type | LED |
| Mode | Positive |
| Foreground Color | Dark |
| Background Color | Light Gray |
Electrical Specifications
| Supply Voltage for Logic Minimum | 3.3V |
| Supply Voltage for Logic Maximum | 5.5V |
| Supply Voltage for Logic Typical | 5V |
| Supply Current Minimum | 50mA |
| Supply Current Maximum | 267mA |
Environmental
| Operating Temperatures | min | max |
|---|---|---|
| Celsius | -20° | 70° |
| Fahrenheit | -4° | 158° |
| Storage Temperatures | min | max |
|---|---|---|
| Celsius | -30° | 80° |
| Fahrenheit | -22° | 176° |
| Humidity | min | max |
|---|---|---|
| Non-condensing | 0% | 90% |
Electronics
| Interface | I2C, Logic Level Serial, RS232, SPI, USB |
Part Change Notice
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Part Change Notice #11097: Display Controller Change
| Products Affected: | CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA835-TML, CFA835-TFK |
| Date Issued: | August 4, 2021 |
| Summary: | Display Controller Change |
| Description: | The display controller, UC1611, is no longer available in the form of bonding on the PCB which is how Crystalfontz has used it for this design. We are designing a drop-in replacement that uses the UC1611 heat seal package, which will continue to be supported, instead of the PCB bonding package. This component package change requires us to alter the PCB by moving some components around so that the heat seal tool can be used without causing damage to any components. Availability of the current hardware version is very limited due to the ongoing worldwide chip shortage. Contact sales@crystalfontz.com for availability and to stay updated for a more accurate ship date. |
| Reason: | UC1611 is no longer supported in the PCB bondable package. |
| Availability: | Fourth-quarter of 2021. If you would like samples when it becomes available, please contact sales@crystalfontz.com. |
Part Change Notice #11083: Firmware Update
| Products Affected: | CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA835-TML, CFA835-TFK |
| Date Issued: | April 27, 2021 |
| Summary: | Firmware Update |
| Description: | Manufacturing changes for internal process improvements and updating the build instructions so that the serial number is properly returned when using command h01. Hardware Version Change: the hardware version is not changing Firmware Version Change: the firmware version is not changing |
| Reason: | The serial number was not being stored properly in the module's bootloader at the time of manufacturing. |
| Availability: | The update will go into effect in May of 2021. |
Part Change Notice #11068: Updating the hardware and firmware to accommodate a new LCD controller.
| Products Affected: | CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA835-TML, CFA835-TFK |
| Date Issued: | October 12, 2020 |
| Summary: | Updating the hardware and firmware to accommodate a new LCD controller. |
| Description: | These changes are being made to the hardware for both the CFA735TFK and TML variants and 835 TFK and TML variants of displays: The hardware and firmware now support the new LCD controller The hardware has an improved ADC circuit for GPIO5 and GPIO6 835 only: The firmware has been updated with new features including Live Display, analog to digital interpretation on GPIO5 and GPIO6, closed loop temperature control. The new datasheets will have more information on these changes. |
| Reason: | The LCD controller went end-of-life and a replacement is needed. |
| Impact: | This is intended as a drop-in replacement. If the new features listed for the 835 are not wanted, a field upgrade kit that supports the new controller without the new features is available. |
| Recommendation: | Request samples to validate the new version. |
| Availability: | Available now. |
| Price Change: | Price is subject to change. |
Part Change Notice #11062: Firmware Update Available
| Products Affected: | CFA835-TML, CFA835-TFK |
| Date Issued: | February 11, 2020 |
| Summary: | Firmware Update Available |
| Description: | The firmware is being revised from v1.1 to v1.2 |
| Reason: | To correct an issue when the size of a font file on an SD card exceed the buffer size. The revised firmware will stop reading from the SD card until the buffer can accept the remainder of the file. |
| Impact: | This issue only affected files with very large fonts |
| Recommendation: | Customers who use large fonts should update to the latest firmware. It is recommended that any user who upgrades to the new firmware test the upgrade in their system before upgrading all modules. |
| Availability: | The revised firmware is available now in a field upgrade kit. https://www.crystalfontz.com/products/document/4216/835_firmware_1v2_field_upgradekit.zip |
| Price Change: | N/A |
Product Update #11055: CFA835 Firmware Version 1.1 is now available. Firmware update to correct a USB data handling issue.
| Products Affected: | CFA835-TML, CFA835-TFK |
| Date Issued: | October 31, 2019 |
| Summary: | CFA835 Firmware Version 1.1 is now available. Firmware update to correct a USB data handling issue. |
| Description: | Fixed an issue with the USB data handling, primarily affecting the command 40 (0x28) subcommand 2 “Send Image Data to Display from Host.” Other USB data throughput improvements were also made. |
| Impact: | The main effect of these changes is that command packets sent via USB may have slightly different reply times depending on the type of packet. The firmware revision number has also incremented, as such the command 1 (0x01) “Get Module Information” will return “CFA835:hX.X:f1.1” |
| Availability: | The firmware is available now. Upgrade information is included in the datasheet. |
Part Change Notice #10959: As part of our continuous improvement program, the CFA735 and CFA835 series displays are being revised.
| Products Affected: | CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA735-YYK-KR, CFA735-YYK-KT, CFA835-TML, CFA835-TFK, CFA835-YYK |
| Date Issued: | July 12, 2018 |
| Summary: | As part of our continuous improvement program, the CFA735 and CFA835 series displays are being revised. |
| Description: | Components have been updated to ensure the long-term availability of the modules. The LCD glass used has been changed to improve contrast. |
| Availability: | Samples will be available in November 2018. Last time buys of the current design may be made until January 2019. |
Part Change Notice #10669: CFA635, CFA735, and CFA835 displays with ATX (power on / off / reset) functionality enabled serial cable bundle change.
| Products Affected: | CFA835-TML, CFA835-TFK, CFA835-YYK |
| Date Issued: | July 29, 2015 |
| Summary: | CFA635, CFA735, and CFA835 displays with ATX (power on / off / reset) functionality enabled serial cable bundle change. |
| Description: | As part of our continuous improvement process, CFA635 KS, CFA735 KT, and CFA835 display modules with the ATX (power on / off / reset) functionality enabled will have their RS-232 SERIAL cable bundle options changed from a serial cable and WRPWRY24 to a serial cable and a WRPWRY25. With TX (power on / off / reset) functionality enabled, additional |
| Reason: | The WRPWRY24 is a power only cable and suitable for powering the CFA635, CFA735, and CFA835 when properly configured. When the displays are configured for ATX (power on / off / reset) functionality additional connections are necessary for proper operation. The WRPWRY25 offers the additional connections. |
| Impact: | Full functionality will now be available as the part is shipped. |
| Availability: | Immediate. |
| Price Change: | There is no price change associated with this change. |
Product Update #10582: (New Product) CFA835-TFK
| New Product: | CFA835-TFK |
| Date Issued: | February 3, 2014 |
| Summary: | (New Product) CFA835-TFK |
| Description: | Intelligent USB LCD Modules: USB+Serial Graphic LCD Module, Keypad, White LED Backlight, FSTN Positive, Transflective, -20°C to +70°C, 12:00. |
For fan control and temperature sensing, use with:
For "full swing" serial interface, use with:
For reference only. For design purposes, please use the specifications in the datasheet.
