USB LCD Displays
20x4 Character RS232 Display Module
Part Number: CFA735-TFK-KT
The CFA735-TFK-KT is a CFA735-TFK-KR with a CFA-RS232 level translator board attached for Full Swing RS232. Use this module for an embedded controller or host system with a "real" RS232 serial port (-5v to +5v "Full Swing" serial interface) available.
Part of the CFA735 family of intelligent display modules, the CFA735-TFK-KT can make a powerful and customizable addition to your product. With an attractive stainless-steel bezel, six-button keypad, GPIOs, LEDs, and memory this module can leverage the command set supported by Crystalfontz to display system status information, receive user input via the keypad, monitor temperatures and control fans using the optional FBSCAB, replace a systems power-on and power-off buttons, and much more. Alternately, write custom firmware for the onboard STM32F401 microcontroller.
Crystalfontz offers a range of intelligent displays. Unsure which display to choose? Compare all of our intelligent display modules.
The CFA735 modules include an STM32F401 microcontroller and use a buck-boost switching supply to allow for a wide supply voltage range which makes these modules perfect for use in embedded systems. The CFA735-TFK-KT supports USB communication as well as RS232 serial (-5v to +5v). The two interfaces can be used simultaneously to communicate with two different host systems.
The display on this module is a 20x4 character display with a light background and dark font. For similar module with a graphic display, see the CFA835-TFK. The CFA735 family is designed to fit into a 1U rackmount case. Options for mounting brackets can be seen by clicking "Customize and add to Cart."
Key Features:
Our CFA835-TFK is the exact same hardware, with graphic capabilities and direct access to the SD Card.
Currently Shipping: HW Version 2.0, FW Version 1.3
Part of the CFA735 family of intelligent display modules, the CFA735-TFK-KT can make a powerful and customizable addition to your product. With an attractive stainless-steel bezel, six-button keypad, GPIOs, LEDs, and memory this module can leverage the command set supported by Crystalfontz to display system status information, receive user input via the keypad, monitor temperatures and control fans using the optional FBSCAB, replace a systems power-on and power-off buttons, and much more. Alternately, write custom firmware for the onboard STM32F401 microcontroller.
Crystalfontz offers a range of intelligent displays. Unsure which display to choose? Compare all of our intelligent display modules.
The CFA735 modules include an STM32F401 microcontroller and use a buck-boost switching supply to allow for a wide supply voltage range which makes these modules perfect for use in embedded systems. The CFA735-TFK-KT supports USB communication as well as RS232 serial (-5v to +5v). The two interfaces can be used simultaneously to communicate with two different host systems.
The display on this module is a 20x4 character display with a light background and dark font. For similar module with a graphic display, see the CFA835-TFK. The CFA735 family is designed to fit into a 1U rackmount case. Options for mounting brackets can be seen by clicking "Customize and add to Cart."
Key Features:
- LED backlit 20x4 character LCD
- FSTN Positive
- Transflective
- 12:00 viewing direction (best from above)
- White Backlight
- LCD characters are contiguous in both X and Y directions allowing "gapless" bar graphs
- Integrated 6-button translucent silicon keypad
- Screened legend on keys
- LED backlit (white)
- Fully decoded keypad: any key combination is valid and unique
- Four bicolor (red + green) LEDs
- LED brightness is software controllable and allows mixing the LEDs to produce intermediary colors (yellow, amber, etc.)
- USB and RS232
- Includes CFARS-232 daughter board for Full-Swing serial communications.
- Robust packet based communications protocol with 16-bit CRC.
- Compact size: fits in a 1U rack mount case (37.5mm overall height)
- Non-volatile memory capability ("EEPROM"):
- Customize the "power-on" display and LED settings.
- 16-byte "scratch" register for storing IP, netmask, system serial number
- Run STM32 embedded applications on the CFA735 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 CFA735 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
- SLED or drive bay bracket for mounting into a system
Our CFA835-TFK is the exact same hardware, with graphic capabilities and direct access to the SD Card.
Currently Shipping: HW Version 2.0, FW Version 1.3
Product Variants
Logic Level Serial/USB
RS232/USB
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Datasheet
Previous Versions of Datasheets
CFA735-xxx-KT Data Sheet Release Date 2012-10-12.pdf
(Datasheet V 2012-10-12, Hardware 1v0, Firmware 0vB)
(Datasheet V 2012-10-12, Hardware 1v0, Firmware 0vB)
CFA735-xxx-KT Data Sheet 0v9 Preliminary.pdf
(Datasheet V 0v9 Preliminary, Hardware 0v9, Firmware 0v9)
(Datasheet V 0v9 Preliminary, Hardware 0v9, Firmware 0v9)
Compliance Documents
TECHNICAL SPECS
Physical Characteristics
| Characters x Lines | 20 x 4 |
| Module Overall | width | height | depth |
|---|---|---|---|
| millimeters | 142 | 38 | 34.6 |
| inches | 5.591 | 1.496 | 1.362 |
| *depth doesn't include Keypad | |||
| Diagonal Dimension | 3.19" |
| Viewing Area | width | height |
|---|---|---|
| millimeters | 83.1 | 27.54 |
| inches | 3.272 | 1.084 |
| 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 | 57g |
| Keystroke Travel | 2.4mm |
| Keypad Depth | 12:00mm |
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 Maximum | 5.5V |
| Module Connector Pitch | 2.54mm |
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 | RS232, USB |
Part Change Notice
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Part Change Notice #11248: H1 and H2 Header Change
Part Change Notice #11245: Keypad LED, H1 Header, and Polarizer Change
Product Update #11111: PCN 11097 is now in effect
| Products Affected: | CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA835-TML, CFA835-TFK |
| Date Issued: | January 17, 2022 |
| Summary: | PCN 11097 is now in effect |
| Description: | PCN 11097 has been completed and is now in effect. Please refer to PCN 11097 for more information. Please submit any questions to support@crystalfontz.com. |
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
Part Change Notice #11070: Updating the firmware from v1.0 to v1.2.
Part Change Notice #11068: Updating the hardware and firmware to accommodate a new LCD controller.
Part Change Notice #10959: As part of our continuous improvement program, the CFA735 and CFA835 series displays are being revised.
Part Change Notice #10658: Deprecation of "Drive Bay Kit Configurator" / New part numbers for drive bay kits.
| Products Affected: | CFA631-RMF-KU, CFA633-YYB-KS, CFA633-TMC-KS, CFA633-RMC-KS, CFA633-YYB-KU, CFA633-TMC-KU, CFA633-RMC-KU, CFA635-YYE-KS, CFA635-TMF-KS, CFA635-TFE-KS, CFA635-TMF-KL, CFA635-TFE-KL, CFA631-TMF-KU, CFA635-TFE-KU, CFA635-YYE-KL, CFA635-TMF-KU, CFA635-YYE-KU, DS635-AL, DS635-BG, DS635-BK, DS635-AK, CFA533-YYH-KS, CFA533-YYH-KU, CFA533-TMI-KS, CFA533-TMI-KU, CFA533-YYH-KL, CFA533-TMI-KL, CFA533-YYH-KC, CFA533-TMI-KC, CFA533-YYH-KI, CFA633-YYH-KS, CFA633-TMI-KS, CFA633-YYH-KU, CFA633-TMI-KU, CFA632-YFH-KS, CFA632-YDI-KS, CFA632-YFH-KU, CFA632-YDI-KU, CFA634-TFH-KS, CFA634-TMI-KS, CFA634-YFH-KS, CFA634-YDI-KS, CFA634-TFH-KU, CFA634-TMI-KU, CFA634-YFH-KU, CFA634-YDI-KU, CFA633-RDI-KU, CFA633-RDI-KS, CFA533-TFH-KU, CFA533-TFH-KS, CFA633-TFH-KU, CFA633-TFH-KS, CFA533-TFH-KL, CFA533-TFH-KC, CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA735-YYK-KR, CFA735-YYK-KT, CFA632-YDI-KL, CFA632-YDI-KN, CFA632-YDI-KC, CFA632-YDI-KP, CFA632-YFH-KL, CFA632-YFH-KN, CFA632-YFH-KC, CFA632-YFH-KP, CFA634-YDI-KC, CFA634-TMI-KC, CFA634-YFH-KC, CFA634-TFH-KC, CFA634-YFH-KL, CFA634-TFH-KL, CFA634-TMI-KL, CFA634-YDI-KL, CFA634-TFH-KP, CFA634-YFH-KP, CFA634-TMI-KP, CFA634-YDI-KP, CFA634-TFH-KN, CFA634-YFH-KN, CFA634-TMI-KN, CFA634-YDI-KN, CFA631P-TMF-KU |
| Date Issued: | July 1, 2015 |
| Summary: | Deprecation of "Drive Bay Kit Configurator" / New part numbers for drive bay kits. |
| Description: | Starting August 1, 2015 the "Drive Bay Kit Configurator" located at https://www.crystalfontz.com/products/select_kit.html will no longer be functional for ordering one of our Serial or USB displays (CFA533, CFA631, CFA632, CFA633, CFA634, CFA635, and CFA735) in a bracket or SLED. This functionality is being moved to the Customize and Add to Cart process when checking out. This will allow for further customization by our customers to better fit their needs. This change will eliminate the current "kits", but will add options not previously available such as pre-configured ATX functionality, and ALL the currently available interfaces will be orderable in a drive bay bracket or SLED. The new part numbers will have the bracket / SLED and overlay type as a PREFIX to the configured part number. The choice for bracket / SLED to a display order will be via the cart options. Our CFA835 displays were introduced with these configuration options. To see how the new options will look, and what the new part numbers will look like, please see one of our CFA835 parts: https://www.crystalfontz.com/cart/addtocart.php?product_id=2277&qty=1 NOTE: The SLED is only available for the CFA635, CFA735, and CFA835 products. |
| Reason: | As part of our continuous improvement process, we are integrating the ordering of displays in drive bay and SLED kits as part of the display ordering process. |
| Impact: | Drive bay kits in their current configuration will no longer be available. |
| Recommendation: | Place orders prior to 2015-08-01 for upcoming production needs via our website or by contacting our logistics department via email: sales@crystalfontz.com, or by calling 1-888-206-9720 (International call +1-509-892-1200). After the 2015-08-01, please contact our engineering department via support@crystalfontz.com to assist you with ordering your bracket / SLED kits. |
| Availability: | Starting 2015-08-01, the bracket and SLED options for our serial and USB display will be part of the ordering process for the displays |
| Price Change: | Pricing bracket / SLED configurations will reflect manufacturing costs. |
Product Update #10607: Price change for CFA735 based parts, effective 2014-09-01
Product Update #10429: Hardware version update from 0vA to 1v0.
Part Change Notice #10401: CFA735 family firmware 0vB
| Products Affected: | CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA735-YYK-KR, CFA735-YYK-KT |
| Date Issued: | February 3, 2012 |
| Summary: | CFA735 family firmware 0vB |
| Last revision: | 0vA |
| Description: | As part of our continuous improvement process, a new version of the CFA735 firmware is being released to address possible functional and performance issues. |
| Reason: | Corrects the RAM Layout for the STM32F103RC microcontroller. |
| Impact: | Low. |
| Recommendation: | We are recommending that all CFA735 modules be updated to 0vB firmware as soon as possible. NOTE: 0vB firmware requires 0vA hardware. See PCN 10400. |
| Availability: | CFA735 modules shipped from Crystalfontz America Inc, on or after 2012-02-06 |
| Price Change: | This firmware update does not effect the pricing of the CFA735 family. |
Part Change Notice #10400: CFA735 family hardware 0vA
| Products Affected: | CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA735-YYK-KR, CFA735-YYK-KT |
| Date Issued: | January 31, 2012 |
| Summary: | CFA735 family hardware 0vA |
| Last revision: | 0v9 |
| Description: | As part of our continuous improvement process, a new version of the CFA735 hardware is being released to address functional and performance issues. There is a supporting firmware revision for this hardware release. See PCN 10399. |
| Reason: | A 1MΩ 0603 resistor has been added at RC2 in support of fixing and extraneous byte received by the host when using the serial interface after a module reset. There is additional support for this fix in firmware 0vA. |
| Impact: | All CFA735 family modules are affected with this hardware update. |
| Recommendation: | All CFA735 modules that use the serial interface or GPIO lines should update to the new 0vA hardware and supporting firmware. If you require assistance loading the 0603 1MΩ resistor in RC2, please contact support@crystalfontz.com. |
| Availability: | Hardware 0vA and supporting firmware is shipping as standard release as of 2012/01/30. |
| Price Change: | No price change. |
Part Change Notice #10399: CFA735 family firmware 0vA
| Products Affected: | CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA735-YYK-KR, CFA735-YYK-KT |
| Date Issued: | January 31, 2012 |
| Summary: | CFA735 family firmware 0vA |
| Last revision: | 0v9 |
| Description: | As part of our continuous improvement process, a new version of the CFA735 firmware is being released to address functional and performance issues. There is a supporting hardware revision for this firmware release. See PCN 10400. |
| Reason: |
|
| Impact: | All CFA735 family modules are affected with this firmware update. Firmware version 0vA requires supporting hardware version 0vA. |
| Recommendation: | All CFA735 modules that use the serial interface or GPIO lines should update to the new 0vA firmware and supporting hardware. If you require assistance loading the 0603 1MΩ resistor in RC2, please contact support@crystalfontz.com. |
| Availability: | Firmware 0vA and supporting hardware is shipping as standard release as of 2012/01/30. |
| Price Change: | No price change. |
Product Update #10381: (New Product) CFA735-TFK-KT
Product Update #10377: CFA635 to CFA735 Migration
| Products Affected: | CFA635-YYE-KS, CFA635-TMF-KS, CFA635-TFE-KS, CFA635-TMF-KL, CFA635-TFE-KL, CFA635-TFE-KU, CFA635-YYE-KL, CFA635-TMF-KU, CFA635-YYE-KU, CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA735-YYK-KR, CFA735-YYK-KT |
| Date Issued: | January 3, 2012 |
| Summary: | CFA635 to CFA735 Migration |
| Description: | Detailed in formation on migrating from the CFA635 family to the CFA735 family of intelligent modules. The document covers the similarities and differences between the two family of modules. |
| Reason: | Support for the CFA735 product announcement. |
| Recommendation: | All CFA635 users should download and read the document. |
| Availability: | Q1 2012 – Initial run of CFA735 family available. Limited Quantities. Q2 2012 – Production level shipments of CFA735 family. Q3 2012 - CFA735 fully replaces CFA635. |
| Attachment: | CFA735_Migration_doc.pdf (734KB) |
Product Update #10376: Announcing CFA735 family of intelligent LCD modules with CFA635 emulation.
| New Products: | CFA735-TFK-KR, CFA735-TFK-KT, CFA735-TML-KR, CFA735-TML-KT, CFA735-YYK-KR, CFA735-YYK-KT |
| Date Issued: | January 3, 2012 |
| Summary: | Announcing CFA735 family of intelligent LCD modules with CFA635 emulation. |
| Description: | Crystalfontz America Inc. is proud to announce the release of the CFA735 family of intelligent modules. The CFA735 family represents the first of a new generation of our serial and USB interface modules as part of our continuous improvement process. Designed as an easy replacement for the CFA635 family of modules, the CFA735 family is a significant improvement in capability, capacity, flexibility and usability. The CFA735 family in CFA635 Emulation Mode has native support for simultaneous USB and Serial operation. There is an option to order the CFA735 with the CFA-RS-232-01 level inverter for full-swing RS-232 interfaces. The CFA735 family is available as a bare module, with your choice of internal / external USB cable, or with a serial cable kit (power, internal, and external connectivity). |
| Reason: | The CFA735 in CFA635 emulation mode is being released as a replacement for the CFA635 family of modules. The CFA635 family of modules has reached it's EOL. |
| Impact: | Customers migrating from the CFA635 family should place orders for engineering samples, and qualify as required by established procedures. |
| Availability: | The first run of the CFA735 family is available for immediate shipment in limited quantities. The initial release of the CFA735 family is CFA635 Emulation Mode. Our goal was to allow our customers that have integrated the CFA635 into their systems the ability to migrate to the CFA735 in CFA635 Emulation Mode with the least amount of interruption. Q1 2012 – Initial run of CFA735 family available. Limited Quantities. Q2 2012 – Production level shipments of CFA735 family. Q3 2012 - CFA735 fully replaces CFA635. |
| Price Change: | Please see the individual product pages for current pricing. |
| Attachment: | CFA735_Product_Announcement.pdf (2MB) |
For fan control and temperature sensing, use with:
For reference only. For design purposes, please use the specifications in the datasheet.
