ESP32 LCSC Part Validation

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Verified the ESP32 LCSC part project as ESP32-WROOM-32UE-N16 / LCSC C701346 against the available Espressif/LCSC metadata.
Issues found:
  1. Symbol has suspicious extra GND pin 39
    • Datasheet pin table is a 38-pin module.
    • Project symbol includes GND pin 39, likely intended to represent the center/thermal ground land array.
    • Recommended fix: do not present it as a normal datasheet pin unless the part model explicitly documents it as an exposed/ground pad group. Label it clearly as exposed/center GND land or remove it from the user-facing pin table.
  2. Terminal electrical metadata is too weak
    • All terminals appear to have Pin Type: Unspecified / Terminal Type: unspecified.
    • This affects 3V3, GND, EN, GPIOs, analog/input-only pins, UART pins, and NC pins.
    • Recommended fix: classify pins properly:
      • 3V3: power input
      • GND: ground/passive
      • EN: input/control
      • SENSOR_VP, SENSOR_VN, IO34, IO35: input-only / analog-capable
      • GPIOs: bidirectional
      • NC: no-connect
  3. NC pins are not formally encoded as no-connect
    • Pins 17–22 and 32 are named/grouped as NC, but metadata still appears unspecified.
    • Recommended fix: mark them as true no-connect terminals so ERC/part review handles them correctly.
  4. Footprint pad mapping is mostly consistent, but ambiguous
    • The perimeter pads match the ESP32-WROOM-32UE pin order and land pattern style.
    • However, repeated pad names like GND and NC make mapping ambiguous without explicit pad numbers.
    • Recommended fix: ensure footprint pads carry unique pin-number mapping internally, especially for GND pins 1/15/38, NC pins 17–22/32, and center GND lands.
  5. Footprint/documentation formatting issue
    • One GND pad position appears as -8.75 8.88 while others include mm.
    • Recommended fix: normalize coordinate/unit formatting to -8.75mm 8.88mm.
  6. Key metadata is partially missing
    • LCSC number and datasheet URL are present.
    • Manufacturer/MPN appear inferred rather than clearly set as explicit project properties.
    • Recommended fix: explicitly set:
      • Manufacturer: Espressif
      • MPN: ESP32-WROOM-32UE-N16
      • LCSC: C701346
      • Package/footprint: WIFI-SMD_ESP32-WROOM-32UE
      • Operating voltage: 3.0–3.6 V, nominal 3.3 V
      • Temperature: -40°C to +85°C
Overall: the part identity and main pin/footprint geometry look broadly correct, but the symbol/terminal metadata needs cleanup before this is a high-quality reusable library part.
Fix part metadata
Run part review
Check footprint geometry
Document verification
Prepare reusable component
Sign up to send

Files

Pins

Symbol

Layout

Preview

IO34
RXD0
IO27
IO15
IO19
NC
IO17
IO23
TXD0
IO35
IO33
GND
IO32
NC
NC
SENSOR_VP
IO22
GND
Pin Number
39
IO25
IO0
EN
IO21
IO14
IO26
GND
Pin Number
39
IO18
IO16
GND
NC
GND
Pin Number
39
GND
Pin Number
39
NC
IO12
3V3
GND
Pin Number
39
NC
NC
IO13
GND
IO2
SENSOR_VN
GND
Pin Number
39
GND
IO5
IO4
GND
Pin Number
39
GND
Pin Number
39
ESP32-WROOM-32UE-N16 Pin Groups
Source checked: Espressif ESP32-WROOM-32E / ESP32-WROOM-32UE datasheet, Section 3 / Table 3: Pin Definitions. The datasheet states ESP32-WROOM-32E and ESP32-WROOM-32UE share the same 38-pin layout.
Each physical pin is assigned to exactly one primary functional group below, so no pin is duplicated across groups.

Table

GroupPinsWhy grouped here
Power2: 3V3Main 3.3 V module supply input
Ground1: GND, 15: GND, 38: GNDGround / return pins
Control / Enable3: ENChip enable / shutdown control; should not be left floating
Analog Input Only4: SENSOR_VP, 5: SENSOR_VN, 6: IO34, 7: IO35Input-only GPIO/ADC-capable pins
RTC / ADC / Touch GPIO8: IO32, 9: IO33, 10: IO25, 11: IO26, 12: IO27, 13: IO14, 14: IO12, 16: IO13, 23: IO15, 24: IO2, 25: IO0, 26: IO4General GPIO pins with ADC/RTC/touch functions; also include several boot/strapping-capable pins
Digital GPIO / UART / SPI / EMAC27: IO16, 28: IO17, 29: IO5, 30: IO18, 31: IO19, 33: IO21, 34: RXD0, 35: TXD0, 36: IO22, 37: IO23General digital I/O pins with UART/SPI/EMAC alternate functions
No Connect17: NC, 18: NC, 19: NC, 20: NC, 21: NC, 22: NC, 32: NCPins marked NC / not for user connection in the module pin table
Pin-by-Pin Assignment

Table

Pin No.Pin NamePrimary GroupDatasheet functions / notes
1GNDGroundGround
23V3PowerPower supply
3ENControl / EnableHigh: on; low: off; do not leave floating
4SENSOR_VPAnalog Input OnlyGPIO36, ADC1_CH0, RTC_GPIO0
5SENSOR_VNAnalog Input OnlyGPIO39, ADC1_CH3, RTC_GPIO3
6IO34Analog Input OnlyGPIO34, ADC1_CH6, RTC_GPIO4; input-only
7IO35Analog Input OnlyGPIO35, ADC1_CH7, RTC_GPIO5; input-only
8IO32RTC / ADC / Touch GPIOGPIO32, XTAL_32K_P, ADC1_CH4, TOUCH9, RTC_GPIO9
9IO33RTC / ADC / Touch GPIOGPIO33, XTAL_32K_N, ADC1_CH5, TOUCH8, RTC_GPIO8
10IO25RTC / ADC / Touch GPIOGPIO25, DAC_1, ADC2_CH8, RTC_GPIO6, EMAC_RXD0
11IO26RTC / ADC / Touch GPIOGPIO26, DAC_2, ADC2_CH9, RTC_GPIO7, EMAC_RXD1
12IO27RTC / ADC / Touch GPIOGPIO27, ADC2_CH7, TOUCH7, RTC_GPIO17, EMAC_RX_DV
13IO14RTC / ADC / Touch GPIOGPIO14, ADC2_CH6, TOUCH6, RTC_GPIO16, MTMS, HSPICLK, HS2_CLK, SD_CLK, EMAC_TXD2
14IO12RTC / ADC / Touch GPIOGPIO12, ADC2_CH5, TOUCH5, RTC_GPIO15, MTDI, HSPIQ, HS2_DATA2, SD_DATA2, EMAC_TXD3
15GNDGroundGround
16IO13RTC / ADC / Touch GPIOGPIO13, ADC2_CH4, TOUCH4, RTC_GPIO14, MTCK, HSPID, HS2_DATA3, SD_DATA3, EMAC_RX_ER
17NCNo ConnectGPIO6–GPIO11 are connected to onboard SPI flash and are not led out
18NCNo ConnectGPIO6–GPIO11 are connected to onboard SPI flash and are not led out
19NCNo ConnectGPIO6–GPIO11 are connected to onboard SPI flash and are not led out
20NCNo ConnectGPIO6–GPIO11 are connected to onboard SPI flash and are not led out
21NCNo ConnectGPIO6–GPIO11 are connected to onboard SPI flash and are not led out
22NCNo ConnectGPIO6–GPIO11 are connected to onboard SPI flash and are not led out
23IO15RTC / ADC / Touch GPIOGPIO15, ADC2_CH3, TOUCH3, MTDO, HSPICS0, RTC_GPIO13, HS2_CMD, SD_CMD, EMAC_RXD3
24IO2RTC / ADC / Touch GPIOGPIO2, ADC2_CH2, TOUCH2, RTC_GPIO12, HSPIWP, HS2_DATA0, SD_DATA0
25IO0RTC / ADC / Touch GPIOGPIO0, ADC2_CH1, TOUCH1, RTC_GPIO11, CLK_OUT1, EMAC_TX_CLK
26IO4RTC / ADC / Touch GPIOGPIO4, ADC2_CH0, TOUCH0, RTC_GPIO10, HSPIHD, HS2_DATA1, SD_DATA1, EMAC_TX_ER
27IO16Digital GPIO / UART / SPI / EMACGPIO16, HS1_DATA4, U2RXD, EMAC_CLK_OUT
28IO17Digital GPIO / UART / SPI / EMACGPIO17, HS1_DATA5, U2TXD, EMAC_CLK_OUT_180
29IO5Digital GPIO / UART / SPI / EMACGPIO5, VSPICS0, HS1_DATA6, EMAC_RX_CLK
30IO18Digital GPIO / UART / SPI / EMACGPIO18, VSPICLK, HS1_DATA7
31IO19Digital GPIO / UART / SPI / EMACGPIO19, VSPIQ, U0CTS, EMAC_TXD0
32NCNo ConnectNC
33IO21Digital GPIO / UART / SPI / EMACGPIO21, VSPIHD, EMAC_TX_EN
34RXD0Digital GPIO / UART / SPI / EMACGPIO3, U0RXD, CLK_OUT2
35TXD0Digital GPIO / UART / SPI / EMACGPIO1, U0TXD, CLK_OUT3, EMAC_RXD2
36IO22Digital GPIO / UART / SPI / EMACGPIO22, VSPIWP, U0RTS, EMAC_TXD1
37IO23Digital GPIO / UART / SPI / EMACGPIO23, VSPID, HS1_STROBE
38GNDGroundGround
Notes
  • I intentionally did not duplicate pins across groups, even when a pin has multiple alternate functions.
  • If you want Flux Pin Group properties instead of broader symbol sections, a practical mapping would be: Power, Ground, Control, ADC1_InputOnly, RTC_ADC_TOUCH_GPIO, Digital_Comm_GPIO, and NC.
  • If you want sub-symbol blocks for the schematic symbol, use the same group names above; Power should include both 3V3 and all GND pins.

  • Recommended Primary Pin Groups

  • Pin-by-Pin Assignment

  • Notes