# Anonymous Brown Scramble Suit ## Description Low-Power Dual-Radio Environmental Sensor Node with Robust USB-C Protection ## Project Details - **Owner:** shridharr - **Created:** 11/12/2025 - **Last Updated:** 11/12/2025 - **Visibility:** Public - **Antenna Keepout Area:** Define a dedicated PCB region adjacent to the ESP32-WROOM-32D module for antenna keepout as per module datasheet guidance (minimum: 15 mm x 6 mm extending from the antenna edge, free of copper, traces, and components on all layers). - **Domain:** Consumer Electronics - **PCB Size X:** 58.0 mm - **Connectivity:** Bluetooth - **Domain:** Industrial/Manufacturing - **Connectivity:** WiFi - **Operating Voltage:** 3.3V - **System Architecture:** graph LR USBC["USB-C Input with Protection"] Prot["Power Protection Circuit"] Reg3V3["3.3V Regulator"] MCU["Dual-Radio Wi-Fi/BLE MCU"] Sensor["Temp/Humidity Sensor"] I2CBus["I²C Bus"] Antenna["Antenna Keepout Area"] USBC --> Prot --> Reg3V3 --> MCU MCU --> I2CBus --> Sensor MCU --- Antenna - **PCB Stackup:** Standard 4 Layer - **Power Requirements:** USB - **PCB Size Y:** 22.8 mm ## Key Components ### D1 — [TPD4E02B04DQA](https://www.flux.ai/kicad-part-library/tpd4e02b04dqa.md) - Manufacturer Name: Texas Instruments Inc. - Role Details: Input surge protection for 5 V USB-C input - Role: Protection - Datasheet URL: http://www.ti.com/lit/ds/symlink/tpd4e02b04.pdf - Package or Case Code: USON-10_2.5x1.0mm_P0.5mm - Manufacturer Part Number: TPD4E02B04DQA **Pins:** - G [pin 3] - G [pin 8] - IO1 [pin 1] - IO2 [pin 2] - IO3 [pin 4] - IO4 [pin 5] - NC [pin 7] - NC [pin 6] - NC [pin 9] - NC [pin 10] ### J1 — [2024100002](https://www.flux.ai/adrian95/2024100002.md) - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: 2024100002 - Role: Connector - Role Details: USB Type-C receptacle, right-angle, board-mount for 5 V power input up to 3 A - Manufacturer Name: Molex - Part Type: Connector - Datasheet URL: https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/834/202410002_Pkg_Spec.pdf - Package or Case Code: 2024100002 **Pins:** - CC1 [pin A5] - CC2 [pin B5] - DA- [pin A7] - DA+ [pin A6] - DB- [pin B7] - DB+ [pin B6] - GND1 [pin A1] - GND2 [pin A12] - GND3 [pin B1] - GND4 [pin B12] - RX1- [pin B10] - RX1+ [pin B11] - RX2- [pin A10] - RX2+ [pin A11] - SBU1 [pin A8] - SBU2 [pin B8] - SHIELD1 [pin SH1] - SHIELD2 [pin SH2] - SHIELD3 [pin SH3] - SHIELD4 [pin SH4] - TX1- [pin A3] - TX1+ [pin A2] - TX2- [pin B3] - TX2+ [pin B2] - VBUS1 [pin A4] - VBUS2 [pin A9] - VBUS3 [pin B4] - VBUS4 [pin B9] ### U1 — [ESP32-WROOM-32D](https://www.flux.ai/vasyl/esp32-wroom-32d.md) - Part Type: Microcontroller - License: https://creativecommons.org/licenses/by/4.0/ - Max Input Voltage: 3.6V - Manufacturer Part Number: ESP32-WROOM-32D - Package or Case Code: ESP32-WROOM-32 - Manufacturer Name: Espressif Systems - Datasheet URL: https://www.espressif.com/sites/default/files/documentation/esp32-wroom-32d_esp32-wroom-32u_datasheet_en.pdf - Role Details: Main MCU, Dual-radio Wi-Fi/BLE **Pins:** - 3.3V [pin 2] - AGND [pin 39] - CLK [pin 20] - CMD [pin 19] - EN [pin 3] - GND [pin 38] - GND [pin 15] - GND [pin 1] - 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 32] - RXD0 [pin 34] - SD0 [pin 21] - SD1 [pin 22] - SD2 [pin 17] - SD3 [pin 18] - TXD0 [pin 35] - VN [pin 5] - VP [pin 4] ### U2 — [SI7020-A20-YM0](https://www.flux.ai/adrian95/si7020-a20-ym0.md) - Datasheet URL: https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/2232/Si7020-A20_DS.pdf - Part Type: Sensor - Role Details: Digital temperature/humidity sensor, I²C interface at 3.3V - License: https://creativecommons.org/licenses/by/4.0/ - Package or Case Code: SI7020A20YM0 - Max Input Voltage: 3.6V - Manufacturer Name: Silicon Labs - Manufacturer Part Number: SI7020-A20-YM0 **Pins:** - DNC_1 [pin 3] - DNC_2 [pin 4] - GND [pin 2] - SCL [pin 6] - SDA [pin 1] - TGND [pin 7] - VDD [pin 5] ### U3 — [TPS25940LRVCR](https://www.flux.ai/adrian95/tps25940lrvcr.md) - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.ti.com/lit/ds/symlink/tps25940.pdf - Package or Case Code: QFN50P300X400X80-21N - Manufacturer Part Number: TPS25940LRVCR - Part Type: Integrated Circuit - Max Input Voltage: 6.5V - Role: Protection - Manufacturer Name: Texas Instruments - Role Details: Power-path eFuse for 5 V USB-C input providing reverse-polarity, overvoltage, undervoltage lockout, and overcurrent protection up to 5.3 A **Pins:** - ~FLT [pin 20] - DEVSLP [pin 1] - DVDT [pin 18] - EN [pin 14] - EP [pin 21] - GND [pin 16] - ILIM [pin 17] - IMON [pin 19] - IN_1 [pin 9] - IN_2 [pin 10] - IN_3 [pin 11] - IN_4 [pin 12] - IN_5 [pin 13] - OUT_1 [pin 4] - OUT_2 [pin 5] - OUT_3 [pin 6] - OUT_4 [pin 7] - OUT_5 [pin 8] - OVP [pin 15] - PGOOD [pin 2] - PGTH [pin 3] ### U4 — [MCP1700T-3302E-TT](https://www.flux.ai/adrian95/mcp1700t-3302e-tt.md) - Package or Case Code: SOT-23 - License: https://creativecommons.org/licenses/by/4.0/ - Role: Power Conversion},{ - Manufacturer Part Number: MCP1700T-3302E/TT - Datasheet URL: https://datasheet.octopart.com/MCP1700T-3302E/TT-Microchip-datasheet-532260.pdf - Manufacturer Name: Microchip Technology - Max Input Voltage: 6.5V - Part Type: Integrated Circuit - Role Details: 3.3V LDO regulator for MCU and sensor rail **Pins:** - GND [pin 1] - VI [pin 3] - VO [pin 2] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/shridharr/anonymous-brown-scramble-suit](https://www.flux.ai/shridharr/anonymous-brown-scramble-suit).* --- *Generated from [https://www.flux.ai/shridharr/anonymous-brown-scramble-suit](https://www.flux.ai/shridharr/anonymous-brown-scramble-suit)*