# ESP32 WiFi Water Flow Meter ## Description USB-C powered ESP32 WiFi water flow meter interface for a 3/4 inch PVC ultrasonic RS485 flow sensor, including 12V sensor power, 3.3V logic power, protection, status LEDs, and programming/reset support. ## Project Details - **Owner:** yousifq - **Created:** 8/15/2024 - **Last Updated:** 6/3/2026 - **Visibility:** Public ## Key Components ### D1 — [USBLC6-2SC6](https://www.flux.ai/lcsc/usblc6-2sc6~2e9x.md) - Package or Case Code: SOT-23-6_L2.9-W1.6-P0.95-LS2.8-BL - Manufacturer Name: UMW(友台半导体) - Breakdown Voltage: 6V - Manufacturer Part Number: USBLC6-2SC6 - Maximum Clamping Voltage: 17V - Part Type: ESD Protection Devices - Datasheet URL: https://www.lcsc.com/datasheet/C2687116.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=FlkNBAIDRQULVABfFAVZBgZVFVZYBgZSQ1NeBVIFQlExVlNRTlhdUVdURFlXXzsOAxUeFF5JWBYZEEoKFBINSQcJGk4dAgUUFAk%3D - LCSC Part Number: C2687116 - JLCPCB Part Class: Extended Part - Peak Pulse Current: 5A - Symbol Style: parametric-v1 - Role: ESD Protection - Operating Temperature: -55°C ~ 125°C (TJ) - Role Details: Low capacitance dual-line USB ESD protection - Power: 150W **Pins:** - GND [pin 2] - I/O1 [pin 1] - I/O1 [pin 6] - I/O2 [pin 3] - I/O2 [pin 4] - VBUS [pin 5] ### D2 — [SRDA3.3-6.TBT](https://www.flux.ai/baueralex174/srda3p3-6ptbt~pu.md) - Datasheet URL: https://www.semtech.com/uploads/documents/SRDA3.3-6.pdf - Package or Case Code: SOIC127P600X170-9N - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: SRDA3.3-6.TBT - Role Details: Protects external RS485 A/B lines at sensor connector - Part Type: SRDA3.3-6.TBT - Role: ESD Protection - Manufacturer Name: Semtech Corporation - Compliance: Pb-Free,Halogen Free,RoHS/WEEE Compliant **Pins:** - GND [pin 8] - I/O 1 [pin 1] - I/O 2 [pin 2] - I/O 3 [pin 4] - I/O 4 [pin 5] - I/O 5 [pin 6] - I/O 6 [pin 7] - VREF [pin 3] ### D3 — [SS14](https://www.flux.ai/jecstronic/ss14~ri4.md) - Datasheet URL: https://datasheet.lcsc.com/lcsc/1912111437_Slkor-SLKORMICRO-Elec--SS14_C444721.pdf - Manufacturer Name: Slkor(SLKORMICRO Elec.) - Manufacturer Part Number: SS14 - Part Type: Diode - License: https://creativecommons.org/licenses/by/4.0/ - Role: Boost Rectifier - Role Details: MT3608 12V boost diode **Pins:** - Anode [pin A] - Cathode [pin C] ### F1 — [0805L110WR](https://www.flux.ai/adrian95/0805l110wr~h3i.md) - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: 1.1A hold PTC for ~0.86A estimated peak input current - Datasheet URL: https://www.littelfuse.com/media?resourcetype=datasheets&itemid=3b1fa5dc-24aa-4363-b543-edb057c2fffa&filename=littelfuse_ptc_0805l_datasheet.pdf - Part Type: Fuse - Role: Protection - Manufacturer Part Number: 0805L110WR - Manufacturer Name: Littelfuse Inc. **Pins:** - P1 [pin 1] - P2 [pin 2] ### J1 — [USB4215-03-A](https://www.flux.ai/adrian95/usb4215-03-a~kg3.md) - Role Details: USB-C sink input with CC pull-downs, 5V only no PD - Manufacturer Part Number: USB4215-03-A - Role: Power Input - Datasheet URL: https://gct.co/files/specs/usb4215-spec.pdf - Symbol Style: parametric-v1 - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: USB C - Manufacturer Name: GCT - Package or Case Code: GCT_USB4215-03-A_REVA **Pins:** - CC1 [pin A5] - CC2 [pin B5] - DN1 [pin A7] - DN2 [pin B7] - DP1 [pin A6] - DP2 [pin B6] - GND_A [pin A1_B12] - GND_B [pin B1_A12] - SBU1 [pin A8] - SBU2 [pin B8] - SHIELD [pin SH1] - SHIELD [pin SH4] - SHIELD [pin SH2] - SHIELD [pin SH3] - VBUS_A [pin A4_B9] - VBUS_B [pin B4_A9] ### J2 — [DB127V-5.08-2P-GN-S](https://www.flux.ai/cherepanyadima/db127v-5p08-2p-gn-s~ic.md) - Role Details: External ultrasonic flow sensor connection - Manufacturer Name: DORABO - Role: Field Connector - Manufacturer Part Number: DB127V-5.08-2P-GN-S - Datasheet URL: https://www.lcsc.com/datasheet/C3018698.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=ElhbUlFSRlUNBF0CQlQIBQBUFFILBFEAQVVWUgZWE1gxVlNRQVVdVFRSQ1daVDsOAxUeFF5JWBYZEEoBGA4JCwFIFA4DSA%3D%3D - Part Type: Connector **Pins:** - 1 [pin 1] - 2 [pin 2] ### J3 — [DB127V-5.08-2P-GN-S](https://www.flux.ai/cherepanyadima/db127v-5p08-2p-gn-s~ic.md) - Manufacturer Name: DORABO - Role Details: External ultrasonic flow sensor connection - Role: Field Connector - Manufacturer Part Number: DB127V-5.08-2P-GN-S - Datasheet URL: https://www.lcsc.com/datasheet/C3018698.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=ElhbUlFSRlUNBF0CQlQIBQBUFFILBFEAQVVWUgZWE1gxVlNRQVVdVFRSQ1daVDsOAxUeFF5JWBYZEEoBGA4JCwFIFA4DSA%3D%3D - Part Type: Connector **Pins:** - 1 [pin 1] - 2 [pin 2] ### J4 — [Pin Header 01x06 2.54mm PROGRAMMING CONNECTOR](https://www.flux.ai/zalak201285/pin-header-01x06-2p54mm-programming-connector~ji.md) - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: 3.3V UART programming/debug with EN and BOOT control pins - Part Type: Connector - Role: Programming Header **Pins:** - JTCK [pin 2] - JTDI [pin 1] - JTDO [pin 3] - JTMS [pin 4] - NJTRST [pin 5] - RESET [pin 6] ### LED1 — [BZ-C0603-G3-F1](https://www.flux.ai/lcsc/bz-c0603-g3-f1~v6dg.md) - Part Type: Light Emitting Diodes (LED) - Datasheet URL: https://www.lcsc.com/datasheet/C2833058.pdf - JLCPCB Part Class: Extended Part - Manufacturer Name: baizou(百洲) - Package or Case Code: LED0603-R-RD_GREEN - Role: Status Indicator - Role Details: Power, WiFi, and flow activity indication - LCSC Part Number: C2833058 - Manufacturer Part Number: BZ-C0603-G3-F1 - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - A [pin 1] - K [pin 2] ### LED2 — [BZ-C0603-G3-F1](https://www.flux.ai/lcsc/bz-c0603-g3-f1~v6dg.md) - JLCPCB Part Class: Extended Part - Datasheet URL: https://www.lcsc.com/datasheet/C2833058.pdf - Role: Status Indicator - Part Type: Light Emitting Diodes (LED) - Manufacturer Part Number: BZ-C0603-G3-F1 - LCSC Part Number: C2833058 - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: Power, WiFi, and flow activity indication - Package or Case Code: LED0603-R-RD_GREEN - Manufacturer Name: baizou(百洲) **Pins:** - A [pin 1] - K [pin 2] ### LED3 — [BZ-C0603-G3-F1](https://www.flux.ai/lcsc/bz-c0603-g3-f1~v6dg.md) - Part Type: Light Emitting Diodes (LED) - Datasheet URL: https://www.lcsc.com/datasheet/C2833058.pdf - JLCPCB Part Class: Extended Part - Manufacturer Name: baizou(百洲) - Role Details: Power, WiFi, and flow activity indication - Package or Case Code: LED0603-R-RD_GREEN - Role: Status Indicator - License: https://creativecommons.org/licenses/by/4.0/ - LCSC Part Number: C2833058 - Manufacturer Part Number: BZ-C0603-G3-F1 **Pins:** - A [pin 1] - K [pin 2] ### SW1 — [TS-1088-AR02016](https://www.flux.ai/lcsc/ts-1088-ar02016~e3n1.md) - Part Type: Tactile Switches - LCSC Part Number: C720477 - 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: User Control - JLCPCB Part Class: Extended Part - Manufacturer Name: XUNPU(讯普) - Manufacturer Part Number: TS-1088-AR02016 - Role Details: Momentary switch to ground for reset/boot - 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] ### SW2 — [TS-1088-AR02016](https://www.flux.ai/lcsc/ts-1088-ar02016~e3n1.md) - Manufacturer Part Number: TS-1088-AR02016 - Manufacturer Name: XUNPU(讯普) - JLCPCB Part Class: Extended Part - 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 Details: Momentary switch to ground for reset/boot - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2409302330_XUNPU-TS-1088-AR02016_C720477.pdf - Part Type: Tactile Switches - Role: User Control - LCSC Part Number: C720477 **Pins:** - 1 [pin 1] - 2 [pin 2] ### U1 — [ESP32-WROOM-32E-N16](https://www.flux.ai/jecstronic/esp32-wroom-32e-n16~wqb.md) - Manufacturer Name: Espressif Systems - Role: WiFi MCU - Manufacturer Part Number: ESP32-WROOM-32E-N16 - Part Type: Module - Datasheet URL: https://www.espressif.com/sites/default/files/documentation/esp32-wroom-32e_esp32-wroom-32ue_datasheet_en.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: ESP32 module, UART to RS485 transceiver, status GPIOs, boot/reset support **Pins:** - 3V3 [pin 2] - EN [pin 3] - GND [pin 43] - GND [pin 1] - GND [pin 38] - GND [pin 42] - GND [pin 40] - GND [pin 46] - GND [pin 41] - GND [pin 45] - GND [pin 15] - GND [pin 47] - GND [pin 39] - GND [pin 44] - IO0 [pin 25] - IO12 [pin 14] - IO13 [pin 16] - IO14 [pin 13] - IO15 [pin 23] - IO16 [pin 27] - IO17 [pin 28] - IO18 [pin 30] - IO19 [pin 31] - IO2 [pin 24] - IO21 [pin 33] - IO22 [pin 36] - IO23 [pin 37] - IO25 [pin 10] - IO26 [pin 11] - IO27 [pin 12] - IO32 [pin 8] - IO33 [pin 9] - IO34 [pin 6] - IO35 [pin 7] - IO4 [pin 26] - IO5 [pin 29] - NC [pin 21] - NC [pin 20] - NC [pin 32] - NC [pin 19] - NC [pin 17] - NC [pin 22] - NC [pin 18] - RXD0 [pin 34] - SENSOR_VN [pin 5] - SENSOR_VP [pin 4] - TXD0 [pin 35] ### U2 — [AMS1117-3.3](https://www.flux.ai/vasy_skral/ams1117-33~34.md) - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: 5V to 3.3V logic rail sized for ESP32 WiFi peaks; requires copper for heat spreading - Datasheet URL: http://www.advanced-monolithic.com/pdf/ds1117.pdf - Manufacturer Name: AMS - Manufacturer Part Number: AMS1117-3.3 - Symbol Style: Parametric - Part Type: Integrated Circuit - Role: Voltage Regulator **Pins:** - GND [pin 1] - TAB(VOUT) [pin 4] - VIN [pin 3] - VOUT [pin 2] ### U3 — [MT3608 - 4414693](https://www.flux.ai/kicad-part-library/mt3608-4414693~ao3.md) - Datasheet URL: https://www.olimex.com/Products/Breadboarding/BB-PWR-3608/resources/MT3608.pdf - Role: Boost Regulator - Package or Case Code: SOT-23-6 - Role Details: 5V to 12V sensor rail, assumed 100mA peak sensor load - Manufacturer Part Number: MT3608 **Pins:** - EN [pin 4] - FB [pin 3] - GND [pin 2] - IN [pin 5] - NC [pin 6] - SW [pin 1] ### U4 — [MAX3485ESA+](https://www.flux.ai/lcsc/max3485esaplus~baoy.md) - LCSC Part Number: C1545222 - JLCPCB Part Class: Extended Part - Datasheet URL: https://www.analog.com/media/en/technical-documentation/data-sheets/max3483-max3491.pdf - Role Details: Half-duplex RS485 interface for ultrasonic flow sensor - Manufacturer Part Number: MAX3485ESA+ - Package or Case Code: SO-8_L4.9-W3.9-P1.27-LS6.0-BL - Symbol Style: parametric-v1 - Part Type: Integrated Circuit - Manufacturer Name: MAXIM(美信) - Role: RS485 Transceiver **Pins:** - ~{RE} [pin 2] - A [pin 6] - B [pin 7] - DE [pin 3] - DI [pin 4] - GND [pin 5] - RO [pin 1] - VCC [pin 8] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/yousifq/esp32-wifi-water-flow-meter~3c](https://www.flux.ai/yousifq/esp32-wifi-water-flow-meter~3c).* --- *Generated from [https://www.flux.ai/yousifq/esp32-wifi-water-flow-meter~3c](https://www.flux.ai/yousifq/esp32-wifi-water-flow-meter~3c)*