ESPuino/PCBs/Wemos Lolin D32

Tonuino-PCB based on Wemos' Lolin D32

Attention

This PCB is not yet tested!

Features

• Fits Wemos Lolin D32 (not Lolin32, Lolin D32 pro or Lolin 32 lite!)
• Outer diameter: 55 x 81mm
• JST-PH 2.0-connectors for buttons, rotary encoder, Neopixel, RFID and reset (not 2.54mm pitch!)
• 2.54mm-connectors for MAX98357a and uSD-card-reader
• Mosfet-circuit that switches off MAX98357a, Neopixel, headphone-pcb and uSD-card-reader automatically when deepsleep is active
• All peripherals are solely driven at 3.3V! Keep this especially in mind when choosing uSD-reader. If in doubts use one without voltage-regulator (link below).
• If headphone-pcb is used, MAX98357a is automatically muted when there's a headphone plugged in and vice versa.
• If HEADPHONE_ADJUST_ENABLE is set and a headphone is plugged in, an alternative maximum volume is activated. I added this feature because headphone-pcb makes use of an amp that (probably) "allows" children to damage ears. This maximum volume can be set and re-adjusted via webgui.
• Reset-button

Prerequisites

• If no headphone-pcb is connected, make sure HEADPHONE_ADJUST_ENABLE is not active.
• Make sure to change values of voltage divider's restors. They can be configured in settings.h as rdiv1 and rdiv2 and need to be set to 100k/100k.
• Change VOLTAGE_READ_PIN to 35.

Things to mention

• Better don't solder Lolin D32 directly to the PCB. I recommend to make use of female connectors instead (link below).
• When ordering a LiPo-battery, make sure to use one with deep discharge protection! This is really really really important!!!

Hardware-setup

The heart of my project is an ESP32 on a Wemos Lolin D32 development-board. Make sure to install the drivers for the USB/Serial-chip (CP2102 e.g.).

• MAX98357A (like Adafruit's)
• uSD-card-reader 3.3V only
• RFID-reader
• RFID-tags
• Neopixel-ring
• Rotary Encoder
• Buttons
• Speaker
• uSD-card: doesn't have to be a super-fast one; uC is limiting the throughput. Tested 32GB without any problems.
• JSP PH-2.0-connectors
• Female connector
• (optional) IDC-connector female 6pin for headphone-pcb
• (optional) IDC-connector male 6pin for headphone-pcb
• LiPo-battery (2500 mAh) with connector JST PH 2.0mm

Parts

• 1x IRF530NPbF (N-channel MOSFET)
• 1x NDP6020P (P-channel MOSFET)
• 1x 1k resistor
• 1x 10k resistor
• 2x 100k resistor
• 4x JST-PH2.0-connector (2 Pins)
• 3x JST-PH2.0-connector (3 Pins)
• 1x JST-PH2.0-connector (5 Pins)
• Female connector as socket for Lolin32, uSD-reader and MAX98357a
• (optional for headphone-PCB) 1x IDC-connecor female (6pin)
• (optional for headphone-PCB) 1x IDC-connecor male (6pin)

Where to order?

I ordered my PCBs at jlcpcb. You have to order at least 5 pcs, which is only at 2$ + shipping. It took two weeks to arrive. If you want to have a look at the PCBs first (without having KiCad installed), visit Gerberlook and upload gerber.zip from the Gerberfiles-folder.

Do I need to install KiCad?

Unless you don't want to change anything: no! All you need to provide are the gerberfiles (gerber.zip) to your manufactur (e.g. jlcpcb). However, all Kicad-files used are provided as well.