WiFi Station 2024 Model A

Wemos Lolin32 Lite

WiFi Station 2024 Model A (WS24a) is released in year 2024. It is implemented with the ESP32 Wemos Lolin32 Lite and its clones (board: lolin32_lite).

PS21

The processor is a ESP32-D0WDQ6. It has with 2 rows of 13-pin holes (2 rows of headers are supplied but NOT soldered on).

  1. Great introduction
    https://www.mischianti.org/2021/07/30/esp32-wemos-lolin32-lite-high-resolution-pinout-and-specs/
  2. Micropython
    GitHub - chenull/lolinara: Ini adalah board lolin esp32 yang sudah terinstall micropython punya nara
  3. Great video for hardware geeks
    https://www.youtube.com/watch?v=s2JAqwg4udY
  4. Interesting controversy on the charging circuit
    https://www.youtube.com/watch?v=a9f9vHjQSfQ

Many other Mesh Stations are available if you want soldered in headers or you do not need the built-in battery charger.

Note MS24a is the cheaper "Lite" version, not the "standard" version:

Available Pins Standard version Lite version (MS24a)
3V3 2 1
5V 1
GND 5 1
RX/TX 2
GPIO 21 21

lolin-esp32-lite-pinout

Schematic
sch_lolin32_lite_v1.0.0.pdf (86.5 KB)

Datasheet
Espressif_Systems_01292021_esp32-1991551.pdf (965.5 KB)

PlatformIO

1. Processor

• ESP32-D0WD chip - Dual Core but No Flash
• Xtensa 32-bit LX6 microprocessor
• Floating Point Unit
• DSP instructions (32-bit multiplier, a 32-bit divider etc.)
• 32 interrupt vectors from about 70 interrupt sources
• JTAG for debugging

Internal Memory

• 448 KB of ROM for booting and core functions
• 520 KB of on-chip SRAM (for data and instructions)
• 8 KB of Fast SRAM in RTC
• 8 KB of Slow SRAM in RTC
• 1 Kbit of eFuse: 256 bits for the system (e.g. MAC address) 768 bits for custom applications

Internal Network

• WiFi 802.11b/g/n
• WiFi 802.11n (20 MHz and 40 MHz)
• WiFi up to 150 Mbps of data rate
• WiFi up to 20.5 dBm of transmitting power
• Bluetooth v4.2 BR/EDR and Bluetooth LE
• Bluetooth Class-1, 2, 3 transmit power with dynamic control up to 24 dB

3. Other Components

Flash

Flash Size: 4MByte (32Mbit)

LED

General Purpose LED can be controlled on GPIO-22
Charging LED

3. References

USB

USB Chip

Most models use a CH340G or compatible USB chip, which prefers a 5.0V supply but can handle up to 6.5V maximum, so direct attach to solar panels with 6V output should be OK in most cases.

CH340G Datasheet:

Information on other CH340 chips are available here:

USB Connector

Note MS24a is available with 2 different USB connector types:

  • USB type-c
  • micro USB

ms24.1

Their names are:

  • MS24a - for the USB Type-C version
  • MS24am - for the Micro USB version

Power

LiPo Battery

3.7V Battery

For Mobile or Portable Application 2000 mAh recommended (a new battery at that capacity provides at least 24 hours of power under heavy load)

lipo-2000mah

  • Battery Connector: JST PH 2.0
  • Maximum Charging Current: 500mA

LiPo Charger

Most Wemos Lolin32 Lite and clones has a LTH7R chip onboard as the battery charger, although other chips e.g. LTC4054 might also be used.

LTH7R.PDF (342.1 KB)

Power Savings

ESP32 has numerous modes to help save powr.

Regulator

Power Regulator is ME6211

Solar Panel

Low cost 10W solar panel with microUSB connector can be used to power the device and charge the battery.

solar

Material: Monocrystalline Silicon
Module Efficiency: 21.8%
Product colour : Black, white (optional)
Solar panel material: monocrystalline silicon
Shell material: ABS+PC
Production process : PET lamination
Solar panel power: 30W
Operating voltage: 5V
Open circuit voltage: 6V
Output Current: 830mA Max
Charging interface: Micor USB
Adaptor type: Type C
Waterproof rating: IP65
Cable length: 3 Meters approx.
Size: 172 x 176 x12mm
Weight: 270g

Note the location of the solar dictates the Watts (W) required for individual MS24a, the 10W used above is just an example.