Unexpected Maker FeatherS3D

Product

Product description

This is an ESP32-S3 based Feather board with multiple components:

16MB QSPI Flash
8MB of extra QSPI PSRAM
2 LDOs, LDO2 is user controlled & auto-shuts down in deep-sleep
2x STEMMA QT connectors, 1 on LDO1 and 1 on LDO2
LiPo Battery Charging + JST PH connector
I2C Battery Fuel Gauge
1 Ambient light sensor
1 Low power RGB LED
1 onboard WiFi antenna + 1 u.FL connector
Ultra Low Deep Sleep Current

More information:

Product page: https://esp32s3.com/feathers3d.html

GPIO Pinout

GPIO

Basic Config

substitutions:
  device_name: "feathers3d"

esphome:
  name: ${device_name}

esp32:
  variant: esp32s3
  flash_size: 16MB # FeatherS3[D] has a 16MB flash

psram:
  mode: quad
  speed: 80MHz

logger:
  hardware_uart: USB_CDC

external_components:
  - source: github://Option-Zero/esphome-components
    components: [max17048]

i2c:
  # I2C1 bus, always on
  - id: i2c1
    sda: GPIO8
    scl: GPIO9
    scan: true
    frequency: 400kHz
  # LDO2 must be turned on for using this I2C bus
  # Have in mind LDO2 is always turned off during deep sleep
  - id: i2c2
    sda: GPIO16
    scl: GPIO15
    scan: true
    frequency: 400kHz

switch:
  # LDO2 - Powers i2c2 bus (BME280)
  - platform: gpio
    id: ldo2_switch
    pin: GPIO39
    name: "LDO2"
    restore_mode: ALWAYS_ON # You can set the state of the LDO2 at boot time

output:
  - id: led_blue
    platform: gpio
    pin: GPIO13

light:
  # RGB light, powered by LDO2
  - id: led_rgb
    platform: esp32_rmt_led_strip
    rgb_order: GRB
    chipset: ws2812
    pin: GPIO40
    num_leds: 1
    name: "NeoPixel Light"
  # Blue LED
  - platform: binary
    id: led_blue
    output: led_blue

sensor:
  # Battery voltage, level, discharge rate
  - platform: max17048
    id: max17048_sensor
    i2c_id: i2c1
    address: 0x36
    battery_voltage:
      name: "Battery Voltage"
      id: battery_voltage
    battery_level:
      name: "Battery Level"
      id: battery_level
    rate:
      name: "Battery Discharge Rate"
      id: battery_discharge_rate

  - platform: adc
    pin: GPIO4
    id: ambient_light

Extended config to optimize CPU, Memory and Flash usage – ESP-IDF Framework only

This config is for ESP-IDF framework, as we use specific SDK Config options.

It sets a CPU frequency to 240 MHz
It allocates memory on malloc calls from both internal and PSRAM memory
It allows Mbed TLS to allocate memory in PSRAM
It increases the nvs partition at the cost of reducing the app0/app1 partitions. It gives more space to store persisted variables.

substitutions:
  device_name: "feathers3d"

esphome:
  name: ${device_name}

esp32:
  variant: esp32s3
  # FeatherS3[D] has a 16MB flash on a 240 MHz CPU
  cpu_frequency: 240MHz
  flash_size: 16MB
  # By default, esphome 2025.8.4 generates a partition file that maximizes app0 and app1 partitions
  # and keep nvs partition (used to save global variables) to 446 kB.
  # The partition file, included below, allocate more space to nvs
  # nvs is the partition used by the "preferences" components used to save persisted variables across reboots
  partitions: partitions-16MB-nvs-extended.csv
  framework:
    type: esp-idf
    sdkconfig_options:
      # Enable PSRAM allocation for malloc, so ArduinoJson can allocate big objects in PSRAM
      CONFIG_SPIRAM_USE_MALLOC: y
      # By default, mbedtls only use internal memory.
      # CONFIG_MBEDTLS_DEFAULT_MEM_ALLOC=y tell mbedtls to use malloc.
      # It will therefore be able to allocate memory in PSRAM is CONFIG_SPIRAM_USE_MALLOC is enabled
      CONFIG_MBEDTLS_DEFAULT_MEM_ALLOC: y

psram:
  mode: quad
  speed: 80MHz

logger:
  hardware_uart: USB_CDC

external_components:
  - source: github://Option-Zero/esphome-components
    components: [max17048]

i2c:
  # I2C1 bus, always on
  - id: i2c1
    sda: GPIO8
    scl: GPIO9
    scan: true
    frequency: 400kHz
  # LDO2 must be turned on for using this I2C bus
  # Have in mind LDO2 is always turned off during deep sleep
  - id: i2c2
    sda: GPIO16
    scl: GPIO15
    scan: true
    frequency: 400kHz

switch:
  # LDO2 - Powers i2c2 bus (BME280)
  - platform: gpio
    id: ldo2_switch
    pin: GPIO39
    name: "LDO2"
    restore_mode: ALWAYS_ON # You can set the state of the LDO2 at boot time

output:
  - id: led_blue
    platform: gpio
    pin: GPIO13

light:
  # RGB light, powered by LDO2
  - id: led_rgb
    platform: esp32_rmt_led_strip
    rgb_order: GRB
    chipset: ws2812
    pin: GPIO40
    num_leds: 1
    name: "NeoPixel Light"
  # Blue LED
  - platform: binary
    id: led_blue
    output: led_blue

sensor:
  # Battery voltage, level, discharge rate
  - platform: max17048
    id: max17048_sensor
    i2c_id: i2c1
    address: 0x36
    battery_voltage:
      name: "Battery Voltage"
      id: battery_voltage
    battery_level:
      name: "Battery Level"
      id: battery_level
    rate:
      name: "Battery Discharge Rate"
      id: battery_discharge_rate

  - platform: adc
    pin: GPIO4
    id: ambient_light

Partition file

Into a file named partitions-16MB-nvs-extended.csv next to your ESPHome YAML config, write this content:

otadata,  data,   ota, ,   0x2000,
phy_init, data,   phy, ,   0x1000,
app0,      app, ota_0, , 0x2F0000,
app1,      app, ota_1, , 0x2F0000,
nvs,      data,   nvs, , 0x400000,

This table allocates 2.94 MB for the application and 4 MB for the nvs partition (used to store global variables). It fits for a 16 MB flash. It is possible to reduce the size of the app0 and app1 and increase the nvs partition.

Partition	Size (hex)	Size (bytes)	Size (MB)
otadata	0x2000	8,192	0.008
phy_init	0x1000	4,096	0.004
app0	0x2F0000	3,080,192	2.94
app1	0x2F0000	3,080,192	2.94
nvs	0x400000	4,194,304	4.0
Total		16,366,976	15.6

Product description​

GPIO Pinout​

Basic Config​

Extended config to optimize CPU, Memory and Flash usage – ESP-IDF Framework only​

Partition file​

Product description

GPIO Pinout

Basic Config

Extended config to optimize CPU, Memory and Flash usage – ESP-IDF Framework only

Partition file