hardware:pcb:esp:esp8266-lolinv3-lamp

ESP8266-LolinV3-Lamp

This PCB has been designed to host the components needed to properly drive an addressable led strip (WS2812B) with a NodeMCU Lolin V3 board (ESP8266).

This PCB can be easily embedded in any 3d printable case or lamp and provide the following functionalities:

ESP8266-LolinV3-Lamp v.1.0

  • Switchable power line (for led strip and fan) controllable through pin D1 of the NodeMCU board
  • Footprint and circuit for a Photoresistor
  • Buzzer
  • Pin header for a capacitive button
  • Pin header for LED strip connection
  • Pin header for microphone connection
  • Footprint for a 1000 uF capacitor to properly power the led strip
  • Footprint for DC barrel jack to power the board and the strip
  • Power in pin header
  • Bidirectional logic level converter based on mosfet FDN337N (not working, substituted with dedicated IC in v.2.0) to drive the data pin of the LED strip

The ESP8266-LolinV3-Lamp v.2.0 offers the same functionalities of the board 1.0, plus:

  • Dedicated pin header for fan connection with flyback diode
  • Additional power pin header
  • Dedicated logic level converter IC (SN74AHCT125DR) to drive the data pin of the LED strip

The PCB is meant to be used with a dedicated firmware generated with the ESPHome platform, that is part of the d-diot image since version 1.1.

The schematic and the entire Kicad project are available for download in the dedicated d-diot github repository. In the repository you can find the gerber files of the PCB, so you can easily get 10 boards with about 5€ using an online PCB manufacturer like JLCPCB or PCB way.

Visit the dedicated topic in the forum if you need to know more.

Click the button below to download the complete set (zip) of gerber files necessary for the manufacturing.

Download Gerber ESP8266-LolinV3-Lamp v.1.0

This is how the board looks:

Below the schematics ( pdf format).

ESP8266-LolinV3-Lamp v.1.0 Schematics

Use the interactive BOM tool to see where to place each component

References Value Footprint Quantity
C1 1000uF CP_Radial_D10.0mm_P5.00mm 1
C2 0.1uF C_Disc_D6.0mm_W4.4mm_P5.00mm 1
R1- R2- R3 10K R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal 3
R4 100K R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal 1
R5 470R R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal 1
R6 200R R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal 1
R7 56K R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal 1
R8 R_PHOTO R_LDR_5.0x4.1mm_P3mm_Vertical 1
U1 NodeMCU1.0(ESP-12E) NodeMCU-LoLinV3 1
BZ1 Buzzer Buzzer_12x9.5RM7.6 1
JP1 Jumper_3_Open PinHeader_1x03_P2.54mm_Vertical 1
Q3- Q6 FDN337N SSOT-3 2
Q4 FDN338P SSOT-3 1
Q1 IRLB8721PBF TO-220-3_Vertical 1
Q5 FQP27P06 TO-220-3_Vertical 1
J7 Barrel_Jack BarrelJack_Wuerth_6941xx301002 1
J4 LED PinHeader_1x03_P2.54mm_Vertical 1
J5 BUTTON PinHeader_1x03_P2.54mm_Vertical 1
J2 PWR PinHeader_1x04_P2.54mm_Vertical 1
J6 MIC PinHeader_1x04_P2.54mm_Vertical 1
J1- J3 Conn_01x15_Male PinHeader_1x15_P2.54mm_Vertical 2

The data pin of a WS2812B led strip require 5 volts to be properly driven, but in most cases a direct connection from the ESP8266 GPIO pin, which is 3.3V, should work.

If you are an unlucky (like me with one strip only) the voltage provided by the MCU board is not sufficient and the led strip will not work properly (see here).

The solution is a logic level converter (LLC) circuit that shift the voltage of the GPIO pin from 3.3V to 5V; in the version 1.0 of the esp8266-lolinv3-lamp board this function is provided by the FDN337N Mosfet (Q3) and the resistors R1 and R2.

Unfortunately this kind of LLC is not working well, probably because the switching time of the mosfet is not fast enough to the WS2812B protocol which is very picky about the timing of the signal (see here) and this is why in the second version of the board the LLC circuit has been substituted with a dedicated IC (see this).

The solution proposed in this blog and reported in the image below is working well, so the board v.1.0 is still usable even if you are unlucky.

The diode solution

Click the button below to download the complete set (zip) of gerber files necessary for the manufacturing.

Download Gerber ESP8266-LolinV3-Lamp v.2.0

or order the PCB directly from PCBWay.

Order your board v.2.0 with PCBWay

This is how the board looks:

Below the schematics ( pdf format).

ESP8266-LolinV3-Lamp v.2.0 Schematics

Use the interactive BOM tool to see where to place each component

References Value Footprint Quantity
C1 1000uF CP_Radial_D10.0mm_P5.00mm 1
C2 0.1uF C_Disc_D6.0mm_W4.4mm_P5.00mm 1
R3 10K R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal 1
R4 100K R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal 1
R5 470R R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal 1
R6 200R R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal 1
R7 56K R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal 1
R8 R_PHOTO R_LDR_5.0x4.1mm_P3mm_Vertical 1
D1 1N4007 D_DO-41_SOD81_P10.16mm_Horizontal 1
U1 NodeMCU1.0(ESP-12E) NodeMCU-LoLinV3 1
U2 SN74AHCT125DR SOIC127P600X175-14N 1
BZ1 Buzzer Buzzer_12x9.5RM7.6 1
JP1 Jumper_3_Open PinHeader_1x03_P2.54mm_Vertical 1
Q4 FDN338P SSOT-3 1
Q6 FDN337N SSOT-3 1
Q5 FQP27P06 TO-220-3_Vertical 1
J7 Barrel_Jack BarrelJack_Wuerth_6941xx301002 1
J8 FAN PinHeader_1x02_P2.54mm_Vertical 1
J9 PWR-2 PinHeader_1x02_P2.54mm_Vertical 1
J4 LED PinHeader_1x03_P2.54mm_Vertical 1
J5 BUTTON PinHeader_1x03_P2.54mm_Vertical 1
J2 PWR PinHeader_1x04_P2.54mm_Vertical 1
J6 MIC PinHeader_1x04_P2.54mm_Vertical 1
J1- J3 Conn_01x15_Male PinHeader_1x15_P2.54mm_Vertical 2

In both versions of the boards only one Jumper (JP1) is present:

  • Config A: with a jumper caps short the data pin with the D2 pin to connect the data pin of the led strip directly to the D2 pin of the MCU board, bypassing the LLC converter.
  • Config B: with a jumper caps short the data pin with the LLC pin to connect the data pin of the led strip with the output of the LLC converter

For the board v.1.0 use only the Config A (see here)

The configuration file in yaml format, necessary to generate the firmware with ESPHome, are in the dedicated d-diot github repository.

  • hardware/pcb/esp/esp8266-lolinv3-lamp.txt
  • Last modified: 2020/05/01 10:05
  • by franzunix