This project is sponsered by <\/strong> Inspired by the \u201cCheap Yellow Display<\/a>\u201d board that I used in an earlier project<\/a>, I thought it would be interesting to design a piggy-back board for this display so it can be used in the same easy way as the Cheap Yellow Display.<\/p>\n\n\n\n This way, the maker only has to come up with a fun application and write the software for it, without having to worry about all the hardware connections. To allow external modules, such as sensors, to be connected, the board includes an I2C port (3.3V) and a more universal connector with one GPIO output (GPIO27), two input pins (GPIO34 and GPIO35), 3.3V, GND, and \u2014 via a solder bridge \u2014 5V.<\/p>\n\n\n\n In hindsight, I should also have exposed GPIO19, but that will be included in the next PCB revision.<\/p>\n\n\n\n In the first revision of this board, I used a CP2104 as the USB-to-UART bridge. However, this chip is so small (QFN package) that it is difficult for the average maker to solder by hand. For revision 2, I switched to the much more manageable CH340C bridge (SOIC-16 package).<\/p>\n\n\n\n All remaining components are small, but still easy enough to solder by hand.<\/p>\n\n\n\n One thing that differs from most of my other ESP8266 and ESP32 projects is that I decided to use a USB-to-UART bridge for programming the SoC. Since USB-C has become the new standard, I decided to use that as well. That is why the two 5k1 resistors (R4 and R5) are included. These are used to negotiate the required voltage with the USB hub or computer (5 volts in this case). U1 is an MCP1826S (LDO) capable of delivering up to 1 ampere. However, if you do not have one available, you can also use an LM2937-3.3V or a TC1262-3.3V, since they share the same pinout but provide a lower maximum current (500mA).<\/p>\n\n\n\n U2 is an ESD protection chip that protects the circuit against large voltage spikes. You can safely omit U2, but in that case you must bridge JP1 and JP2 with solder.<\/p>\n\n\n\n SW1 (and R2) and SW2 (and R3) are also not strictly required. If you install them on the board, you can manually reset the SoC or put it into flash mode.<\/p>\n\n\n Using a solder bridge, J2 pin 1 can be connected to VBUS. This allows you to either supply 5 volts from the board to an external system or power the board itself from a system connected to J2.<\/p>\n\n\n\n The external connectors J2 and J3 use a 2.50mm pin pitch. You can choose whatever connector type you prefer. I selected JST-XH connectors because they are relatively compact and the female connectors can easily be assembled by hand. However, you could also use screw terminals or simply solder wires directly to the PCB.<\/p>\n\n\n\n Apart from that, the schematic is fairly straightforward.<\/p>\n\n\n\n After designing the PCB in KiCad, I sent the design to KiCad includes a very convenient add-on that allows this entire process to be completed automatically with a single button press.<\/p>\n\n\n I like working with The PCB quality has consistently been excellent. Clean silkscreen printing, neat solder masks, and professionally finished boards \u2014 even for small prototype orders. That gives me confidence when testing new designs or sharing projects online.<\/p>\n\n\n\n What I personally appreciate most is the speed. In many cases, I receive my PCBs within just a few days. That allows me to iterate faster, fix issues quickly, and keep building without long delays.<\/p>\n\n\n\n For my own projects, Before ordering the PCB, the only remaining choices are the PCB thickness, the PCB color, and the silkscreen color. Because the through-hole USB-C connector has very short pins, I decided to use a 1mm PCB instead of the standard 1.6mm thickness.<\/p>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/03\/inline-PCBWay.png\")
<\/p>\n\n\n\n
Possible applications could include:<\/p>\n\n\n\n\n
Schematic<\/strong><\/h2>\n\n\n
![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/TFT-LCD-DISPLAY-EC-BOARD-1024x707.png\")
<\/a><\/figure>\n<\/div>\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/piggyBack-USB-C.png\")
<\/a><\/figure>\n<\/div>\n\n\n
I selected a 16 pin Through Hole (THT) connector (USB4085-GF-A<\/a>)<\/p>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/USB4085-GF-A_top-300x232.png\")
<\/a><\/figure>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/USB4085-GF-A_bottom.png\")
<\/a><\/figure>\n<\/figure>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/piggyBack-PWR.png\")
<\/a><\/figure>\n<\/div>\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/piggyBack-ESD.png\")
<\/a><\/figure>\n<\/div>\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/piggyBack-J2.png\")
<\/a><\/figure>\n<\/div>\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/piggyBack-J3.png\")
<\/a><\/figure>\n<\/div>\n\n\n for manufacturing. <\/p>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/KiCad-PCBWay-1.png\")
<\/a><\/figure>\n<\/div>\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/piggyBack-KiCad.png\")
<\/a><\/figure>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/TFT_LCD_Display_EC11_top-1024x655.png\")
<\/a><\/figure>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/TFT_LCD_Display_EC11_bottom-1024x655.png\")
<\/a><\/figure>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/TFT_LCD_Display_EC11_top_3D-300x197.png\")
<\/a><\/figure>\n<\/figure>\n\n\n\n because they really understand what makers need. Whenever I design a new ESP32 project, custom PCB, or hardware prototype, I mainly care about two things: high quality and fast delivery. And that\u2019s exactly where stands out for me.<\/p>\n\n\n\n has become my go-to PCB manufacturer!<\/p>\n\n\n\nBill of Materials<\/strong><\/h2>\n\n\n\n
![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/pbb5.png\")
<\/a><\/figure>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/pbb1.png\")
<\/a><\/figure>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/pbb2.png\")
<\/a><\/figure>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/pbb4.jpg\")
<\/a><\/figure>\n\n\n\n![\"\"](\"https:\/\/willem.aandewiel.nl\/wp-content\/uploads\/2026\/05\/pbb3.jpg\")
<\/a><\/figure>\n<\/figure>\n","protected":false},"excerpt":{"rendered":"