# ESP32 Water Level Early Warning System
## Description
ESP32-based water level early warning system using a waterproof ultrasonic level sensor, USB-C power/programming, WiFi alert capability, local buzzer, and status LED indicators.
## Project Details
- **Owner:** nanangmy
- **Created:** 6/2/2026
- **Last Updated:** 6/2/2026
- **Visibility:** Public
## Key Components
### BZ1 — CMI-9653S-SMT-TR
- Role: Alert
- Manufacturer Part Number: CMI-9653S-SMT-TR
- Manufacturer Name: Same Sky
- License: https://creativecommons.org/licenses/by/4.0/
- Datasheet URL: https://componentsearchengine.com/Datasheets/1/CMI-9653S-SMT-TR.pdf
- Role Details: 3V active buzzer controlled by ESP32 through a low-side switch.
- Package or Case Code: CMI9653SSMTTR
- Part Type: Buzzer
**Pins:**
- - [pin 1]
- + [pin 2]
### BZ2 — CMI-9653S-SMT-TR
- License: https://creativecommons.org/licenses/by/4.0/
- Role Details: Receiver-side active buzzer controlled by ESP32 through a low-side switch.
- Manufacturer Name: Same Sky
- Manufacturer Part Number: CMI-9653S-SMT-TR
- Part Type: Buzzer
- Package or Case Code: CMI9653SSMTTR
- Datasheet URL: https://componentsearchengine.com/Datasheets/1/CMI-9653S-SMT-TR.pdf
- Role: Alert
**Pins:**
- - [pin 1]
- + [pin 2]
### D1 — USBLC6-2SC6
- Breakdown Voltage: 6V
- Maximum Clamping Voltage: 17V
- Operating Temperature: -55°C ~ 125°C (TJ)
- Package or Case Code: SOT-23-6_L2.9-W1.6-P0.95-LS2.8-BL
- Peak Pulse Current: 5A
- Manufacturer Part Number: USBLC6-2SC6
- LCSC Part Number: C2687116
- JLCPCB Part Class: Extended Part
- Role: Protection
- Manufacturer Name: UMW(友台半导体)
- Role Details: Protects USB 2.0 data lines at the connector.
- Datasheet URL: https://www.lcsc.com/datasheet/C2687116.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=FlkNBAIDRQULVABfFAVZBgZVFVZYBgZSQ1NeBVIFQlExVlNRTlhdUVdURFlXXzsOAxUeFF5JWBYZEEoKFBINSQcJGk4dAgUUFAk%3D
- Power: 150W
- Symbol Style: parametric-v1
- Part Type: ESD Protection Devices
**Pins:**
- GND [pin 2]
- I/O1 [pin 1]
- I/O1 [pin 6]
- I/O2 [pin 3]
- I/O2 [pin 4]
- VBUS [pin 5]
### D2 — USBLC6-2SC6
- Power: 150W
- Symbol Style: parametric-v1
- Role Details: Protects receiver USB 2.0 D+/D- lines at J2.
- Part Type: ESD Protection Devices
- Role: Protection
- Datasheet URL: https://www.lcsc.com/datasheet/C2687116.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=FlkNBAIDRQULVABfFAVZBgZVFVZYBgZSQ1NeBVIFQlExVlNRTlhdUVdURFlXXzsOAxUeFF5JWBYZEEoKFBINSQcJGk4dAgUUFAk%3D
- Manufacturer Name: UMW(友台半导体)
- JLCPCB Part Class: Extended Part
- Manufacturer Part Number: USBLC6-2SC6
- LCSC Part Number: C2687116
- Peak Pulse Current: 5A
- Maximum Clamping Voltage: 17V
- Operating Temperature: -55°C ~ 125°C (TJ)
- Package or Case Code: SOT-23-6_L2.9-W1.6-P0.95-LS2.8-BL
- Breakdown Voltage: 6V
**Pins:**
- GND [pin 2]
- I/O1 [pin 1]
- I/O1 [pin 6]
- I/O2 [pin 3]
- I/O2 [pin 4]
- VBUS [pin 5]
### J1 — UJ20-C-H-G-SMT-2-P16-TR
- Symbol Style: parametric-v1
- Manufacturer Name: Same Sky (Formerly CUI Devices)
- Role: Connector
- Datasheet URL: https://www.sameskydevices.com/product/resource/uj20-c-h-g-smt-2-p16-tr.pdf
- License: https://creativecommons.org/licenses/by/4.0/
- Manufacturer Part Number: UJ20-C-H-G-SMT-2-P16-TR
- Role Details: USB-C sink input carrying VBUS, GND, D+, D-, CC1 and CC2.
- Mount: Surface Mount
- Part Type: Connector
**Pins:**
- CC1 [pin A5]
- CC2 [pin B5]
- DN1 [pin A7]
- DN2 [pin B7]
- DP1 [pin A6]
- DP2 [pin B6]
- GND [pin A1_B12]
- GND__1 [pin B1_A12]
- SBU1 [pin A8]
- SBU2 [pin B8]
- SHIELD [pin SH1]
- SHIELD__1 [pin SH2]
- SHIELD__2 [pin SH3]
- SHIELD__3 [pin SH4]
- VBUS [pin A4_B9]
- VBUS__1 [pin B4_A9]
### J2 — UJ20-C-H-G-SMT-2-P16-TR
- Role Details: Receiver USB-C sink input carrying VBUS, GND, D+, D-, CC1 and CC2.
- Role: Connector
- Symbol Style: parametric-v1
- Part Type: Connector
- Mount: Surface Mount
- Manufacturer Part Number: UJ20-C-H-G-SMT-2-P16-TR
- License: https://creativecommons.org/licenses/by/4.0/
- Datasheet URL: https://www.sameskydevices.com/product/resource/uj20-c-h-g-smt-2-p16-tr.pdf
- Manufacturer Name: Same Sky (Formerly CUI Devices)
**Pins:**
- CC1 [pin A5]
- CC2 [pin B5]
- DN1 [pin A7]
- DN2 [pin B7]
- DP1 [pin A6]
- DP2 [pin B6]
- GND [pin A1_B12]
- GND__1 [pin B1_A12]
- SBU1 [pin A8]
- SBU2 [pin B8]
- SHIELD [pin SH1]
- SHIELD__1 [pin SH2]
- SHIELD__2 [pin SH3]
- SHIELD__3 [pin SH4]
- VBUS [pin A4_B9]
- VBUS__1 [pin B4_A9]
### LED1 — 0603GBD0790S01
- Manufacturer Name: ORIENTAL TECHNOLOGY
- Part Type: LED
- Role Details: Green status LED driven by ESP32 through current-limiting resistor.
- License: https://creativecommons.org/licenses/by/4.0/
- Role: Indicator
- Datasheet URL: https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/4336/0603GBD0790S01.pdf
- Manufacturer Part Number: 0603GBD0790S01
**Pins:**
- A [pin 2]
- K [pin 1]
### LED2 — 0603GBD0790S01
- License: https://creativecommons.org/licenses/by/4.0/
- Role Details: Receiver status LED indicates link/alarm state.
- Manufacturer Part Number: 0603GBD0790S01
- Datasheet URL: https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/4336/0603GBD0790S01.pdf
- Manufacturer Name: ORIENTAL TECHNOLOGY
- Role: Status Indicator
- Part Type: LED
**Pins:**
- A [pin 2]
- K [pin 1]
### Q1 — MMBT3904-TP
- Part Type: Transistor
- Role Details: Low-side BJT switch lets ESP32 control buzzer current without directly driving the load.
- Datasheet URL: https://www.mccsemi.com/pdf/Products/MMBT3904(SOT-23).pdf
- Manufacturer Part Number: MMBT3904-TP
- License: https://creativecommons.org/licenses/by/4.0/
- Role: Switching
- Manufacturer Name: Micro Commercial Co
**Pins:**
- B [pin 1]
- C [pin 3]
- E [pin 2]
### Q2 — MMBT3904-TP
- Part Type: Transistor
- Datasheet URL: https://www.mccsemi.com/pdf/Products/MMBT3904(SOT-23).pdf
- Manufacturer Part Number: MMBT3904-TP
- Role Details: NPN low-side switch for receiver active buzzer.
- License: https://creativecommons.org/licenses/by/4.0/
- Role: Driver
- Manufacturer Name: Micro Commercial Co
**Pins:**
- B [pin 1]
- C [pin 3]
- E [pin 2]
### SW1 — TS-1088-AR02016
- Package or Case Code: SW-SMD_L3.9-W3.0-P4.45
- Product Info Url: https://lcsc.com/product-detail/Tactile-Switches_XUNPU-TS-1088-AR02016_C720477.html
- Manufacturer Part Number: TS-1088-AR02016
- Role Details: Momentary switch pulls ESP32 enable/reset net low.
- Role: Reset
- LCSC Part Number: C720477
- JLCPCB Part Class: Extended Part
- Manufacturer Name: XUNPU(讯普)
- Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2409302330_XUNPU-TS-1088-AR02016_C720477.pdf
- Part Type: Tactile Switches
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### SW2 — TS-1088-AR02016
- Manufacturer Name: XUNPU(讯普)
- Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2409302330_XUNPU-TS-1088-AR02016_C720477.pdf
- Part Type: Tactile Switches
- Role: Bootstrapping
- Product Info Url: https://lcsc.com/product-detail/Tactile-Switches_XUNPU-TS-1088-AR02016_C720477.html
- Package or Case Code: SW-SMD_L3.9-W3.0-P4.45
- LCSC Part Number: C720477
- JLCPCB Part Class: Extended Part
- Manufacturer Part Number: TS-1088-AR02016
- Role Details: Momentary switch pulls GPIO0 low for ESP32 serial download mode.
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### SW3 — TS-1088-AR02016
- LCSC Part Number: C720477
- JLCPCB Part Class: Extended Part
- Manufacturer Part Number: TS-1088-AR02016
- Role Details: Momentary switch pulls receiver ESP32 enable/reset net low.
- Product Info Url: https://lcsc.com/product-detail/Tactile-Switches_XUNPU-TS-1088-AR02016_C720477.html
- Package or Case Code: SW-SMD_L3.9-W3.0-P4.45
- Role: Reset
- Part Type: Tactile Switches
- Manufacturer Name: XUNPU(讯普)
- Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2409302330_XUNPU-TS-1088-AR02016_C720477.pdf
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### SW4 — TS-1088-AR02016
- Part Type: Tactile Switches
- Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2409302330_XUNPU-TS-1088-AR02016_C720477.pdf
- Manufacturer Name: XUNPU(讯普)
- Role Details: Momentary switch pulls receiver GPIO0 low for serial/USB download mode.
- Role: Bootstrapping
- Manufacturer Part Number: TS-1088-AR02016
- LCSC Part Number: C720477
- JLCPCB Part Class: Extended Part
- Package or Case Code: SW-SMD_L3.9-W3.0-P4.45
- Product Info Url: https://lcsc.com/product-detail/Tactile-Switches_XUNPU-TS-1088-AR02016_C720477.html
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### U1 — ESP32-S3-WROOM-1-N16R8
- Role: Compute / Wireless
- Datasheet URL: https://www.mouser.com/datasheet/2/891/esp32_s3_wroom_1_wroom_1u_datasheet_en-2930317.pdf
- Manufacturer Name: Espressif Systems
- Manufacturer Part Number: ESP32-S3-WROOM-1-N16R8
- Part Type: Module
- Symbol Style: parametric-v1
- License: https://creativecommons.org/licenses/by/4.0/
- Role Details: ESP32-S3 module with native USB and WiFi/BLE for sensing, alert logic, and network notification.
**Pins:**
- 3V3 [pin 2]
- EN [pin 3]
- GND_1 [pin 1]
- GND_10 [pin 48]
- GND_11 [pin 49]
- GND_2 [pin 40]
- GND_3 [pin 41]
- GND_4 [pin 42]
- GND_5 [pin 43]
- GND_6 [pin 44]
- GND_7 [pin 45]
- GND_8 [pin 46]
- GND_9 [pin 47]
- IO0 [pin 27]
- IO1 [pin 39]
- IO10 [pin 18]
- IO11 [pin 19]
- IO12 [pin 20]
- IO13 [pin 21]
- IO14 [pin 22]
- IO15 [pin 8]
- IO16 [pin 9]
- IO17 [pin 10]
- IO18 [pin 11]
- IO19 [pin 13]
- IO2 [pin 38]
- IO20 [pin 14]
- IO21 [pin 23]
- IO3 [pin 15]
- IO35 [pin 28]
- IO36 [pin 29]
- IO37 [pin 30]
- IO38 [pin 31]
- IO39 [pin 32]
- IO4 [pin 4]
- IO40 [pin 33]
- IO41 [pin 34]
- IO42 [pin 35]
- IO45 [pin 26]
- IO46 [pin 16]
- IO47 [pin 24]
- IO48 [pin 25]
- IO5 [pin 5]
- IO6 [pin 6]
- IO7 [pin 7]
- IO8 [pin 12]
- IO9 [pin 17]
- RXD0 [pin 36]
- TXD0 [pin 37]
### U2 — AP2112K-3.3TRG1
- Manufacturer Name: Diodes Incorporated
- Part Type: Integrated Circuit
- Manufacturer Part Number: AP2112K-3.3TRG1
- Role: Power Conversion
- License: https://creativecommons.org/licenses/by/4.0/
- Role Details: 3.3V LDO sized for estimated ESP32 prototype load; 600mA max output.
- Datasheet URL: https://www.diodes.com/assets/Datasheets/AP2112.pdf
- Symbol Style: parametric-v1
**Pins:**
- EN [pin 3]
- GND [pin 2]
- NC [pin 4]
- VIN [pin 1]
- VOUT [pin 5]
### U3 — JSN-SR04T-2.0
- Part Type: Sensor
- Role: Sensing
- Datasheet URL: https://www.makerguides.com/wp-content/uploads/2019/02/JSN-SR04T-Datasheet.pdf
- Manufacturer Name: jahankit
- Role Details: 5V waterproof ultrasonic module measuring distance to water surface.
- Manufacturer Part Number: JSN-SR04T-2.0
- License: https://creativecommons.org/licenses/by/4.0/
**Pins:**
- - [pin 6]
- + [pin 5]
- 5V [pin 4]
- ECHO [pin 2]
- GND [pin 1]
- TRIG [pin 3]
### U4 — ESP32-S3-WROOM-1-N16R8
- Manufacturer Name: Espressif Systems
- Datasheet URL: https://www.mouser.com/datasheet/2/891/esp32_s3_wroom_1_wroom_1u_datasheet_en-2930317.pdf
- Role Details: ESP32-S3 receiver node for remote early-warning alarm; receives packets from the sensor transmitter using WiFi/ESP-NOW.
- Manufacturer Part Number: ESP32-S3-WROOM-1-N16R8
- Part Type: Module
- Symbol Style: parametric-v1
- License: https://creativecommons.org/licenses/by/4.0/
- Role: Receiver Compute / Wireless
**Pins:**
- 3V3 [pin 2]
- EN [pin 3]
- GND_1 [pin 1]
- GND_10 [pin 48]
- GND_11 [pin 49]
- GND_2 [pin 40]
- GND_3 [pin 41]
- GND_4 [pin 42]
- GND_5 [pin 43]
- GND_6 [pin 44]
- GND_7 [pin 45]
- GND_8 [pin 46]
- GND_9 [pin 47]
- IO0 [pin 27]
- IO1 [pin 39]
- IO10 [pin 18]
- IO11 [pin 19]
- IO12 [pin 20]
- IO13 [pin 21]
- IO14 [pin 22]
- IO15 [pin 8]
- IO16 [pin 9]
- IO17 [pin 10]
- IO18 [pin 11]
- IO19 [pin 13]
- IO2 [pin 38]
- IO20 [pin 14]
- IO21 [pin 23]
- IO3 [pin 15]
- IO35 [pin 28]
- IO36 [pin 29]
- IO37 [pin 30]
- IO38 [pin 31]
- IO39 [pin 32]
- IO4 [pin 4]
- IO40 [pin 33]
- IO41 [pin 34]
- IO42 [pin 35]
- IO45 [pin 26]
- IO46 [pin 16]
- IO47 [pin 24]
- IO48 [pin 25]
- IO5 [pin 5]
- IO6 [pin 6]
- IO7 [pin 7]
- IO8 [pin 12]
- IO9 [pin 17]
- RXD0 [pin 36]
- TXD0 [pin 37]
### U5 — AP2112K-3.3TRG1
- Role Details: Receiver-only 5V USB to 3.3V LDO for U4, sized for a single ESP32-S3 receiver node.
- License: https://creativecommons.org/licenses/by/4.0/
- Manufacturer Part Number: AP2112K-3.3TRG1
- Part Type: Integrated Circuit
- Symbol Style: parametric-v1
- Datasheet URL: https://www.diodes.com/assets/Datasheets/AP2112.pdf
- Role: Power Conversion
- Manufacturer Name: Diodes Incorporated
**Pins:**
- EN [pin 3]
- GND [pin 2]
- NC [pin 4]
- VIN [pin 1]
- VOUT [pin 5]
*The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/nanangmy/esp32-water-level-early-warning-system~ex](https://www.flux.ai/nanangmy/esp32-water-level-early-warning-system~ex).*
---
*Generated from [https://www.flux.ai/nanangmy/esp32-water-level-early-warning-system~ex](https://www.flux.ai/nanangmy/esp32-water-level-early-warning-system~ex)*