# Random Chocolate R2-D2 ## Description USB-C Powered Wi-Fi Voice Recorder ## Project Details - **Owner:** mani6ue - **Created:** 12/8/2025 - **Last Updated:** 12/8/2025 - **Visibility:** Public - **Power Requirements:** USB - **Storage:** microSD card (removable) - **Compliance:** RoHS - **Connectivity:** WiFi, USB - **Audio Front-End:** Digital MEMS microphone with I2S interface powered from 3.3V rail. - **Human Interface:** Buttons, Display - **Operating Voltage:** 3.3V - **License:** http://solderpad.org/licenses/SHL-2.1/ - **Project Name:** Random Chocolate R2-D2 - **Domain:** Consumer Electronics - **Project Description:** USB-C powered Wi-Fi voice recorder based on ESP32-S3 with I2S MEMS microphone and microSD storage. - **System Architecture Diagram:** ```mermaid flowchart TD USB_C[USB-C Receptacle] --> VBUS[VBUS 5V] VBUS --> Buck[5V to 3.3V Buck Regulator] Buck --> V33[3.3V Power Rail] V33 --> ESP32[ESP32-S3-WROOM-1] ESP32 --> USB[USB D+ D-] ESP32 --> WiFi[Wi-Fi] ESP32 --> SD[MicroSD Card Socket] ESP32 --> I2S[I2S MEMS Microphone] V33 --> MIC_PWR[Microphone Power] V33 --> SD_PWR[SD Card Power] USB_C -->|ESD TVS| Buck USB_C -. CC1 CC2 .-> GND[GND] subgraph Controls and Indicators LED[Status LED] BTN[Pushbutton] end ESP32 --> LED ESP32 --> BTN GND --> ESP32 GND --> Buck GND --> MIC_PWR GND --> SD_PWR ``` - **Primary MCU / Module:** ESP32-S3-WROOM-1 - **Manufacturing Quantity Target:** 10 - **Target Software Stack:** Arduino - **Power Architecture Summary:** USB-C 5V input with ESD protection on VBUS, buck regulator down to 3.3V rail powering ESP32-S3, I2S MEMS microphone, microSD card socket, status LED and button. ## Key Components ### D1 — [USBLC6-2P6](https://www.flux.ai/kicad-part-library/usblc6-2p6.md) - Package: SOT-666 - Datasheet URL: https://www.st.com/resource/en/datasheet/usblc6-2.pdf - Role: Protection - Manufacturer Name: Texas Instruments Inc. - Role Details: ESD/TVS protection for USB VBUS, D+ and D- lines - Package or Case Code: SOT-666 - Manufacturer Part Number: USBLC6-2P6 **Pins:** - GND [pin 2] - I/O1 [pin 6] - I/O1 [pin 1] - I/O2 [pin 3] - I/O2 [pin 4] - VBUS [pin 5] ### D2 — [SML-LX0805GC-TR](https://www.flux.ai/adrian95/sml-lx0805gc-tr.md) - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: SML-LX0805GC-TR - Datasheet URL: https://www.lumex.com/spec/SML-LX0805GC-TR.pdf - Part Type: LED - Role: Indicator - Role Details: Status LED for operational feedback - Manufacturer Name: Lumex Opto/Components Inc. **Pins:** - A [pin 2] - K [pin 1] ### D3 — [PESD5V0L2BT](https://www.flux.ai/lcsc/pesd5v0l2bt.md) - Package or Case Code: SOT-23-3_L2.9-W1.3-P0.95-LS2.4-BR - Manufacturer Name: TECH PUBLIC(台舟) - LCSC Part Number: C2858724 - Manufacturer Part Number: PESD5V0L2BT - Role Details: ESD protection for microSD socket data lines DAT0 and DAT1 - Role: Protection - Package: SOT-23-3_L2.9-W1.3-P0.95-LS2.4-BR - Part Type: Diodes - ESD - JLCPCB Part Class: Extended Part **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### D4 — [PESD5V0L2BT](https://www.flux.ai/lcsc/pesd5v0l2bt.md) - JLCPCB Part Class: Extended Part - Part Type: Diodes - ESD - Role Details: ESD protection for microSD socket data lines DAT2 and DAT3 - Package: SOT-23-3_L2.9-W1.3-P0.95-LS2.4-BR - LCSC Part Number: C2858724 - Manufacturer Part Number: PESD5V0L2BT - Manufacturer Name: TECH PUBLIC(台舟) - Package or Case Code: SOT-23-3_L2.9-W1.3-P0.95-LS2.4-BR - Role: Protection **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### D5 — [PESD5V0L2BT](https://www.flux.ai/lcsc/pesd5v0l2bt.md) - Manufacturer Part Number: PESD5V0L2BT - LCSC Part Number: C2858724 - Role: Protection - Manufacturer Name: TECH PUBLIC(台舟) - Package or Case Code: SOT-23-3_L2.9-W1.3-P0.95-LS2.4-BR - JLCPCB Part Class: Extended Part - Part Type: Diodes - ESD - Package: SOT-23-3_L2.9-W1.3-P0.95-LS2.4-BR - Role Details: ESD protection for microSD socket control lines CLK and CMD **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] ### J1 — [MEM2067-02-180-00-A](https://www.flux.ai/adrian95/mem2067-02-180-00-a.md) - Role Details: microSD card socket for removable storage - Manufacturer Name: GCT - Manufacturer Part Number: MEM2067-02-180-00-A - Package: Surface Mount, Right Angle - Role: Connector - Part Type: Connector - Datasheet URL: https://gct.co/files/specs/mem2067-spec.pdf - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - CD/DAT3 [pin 2] - CLK [pin 5] - CMD [pin 3] - DAT0 [pin 7] - DAT1 [pin 8] - DAT2 [pin 1] - SHIELD [pin 12] - SHIELD [pin 9] - SHIELD [pin 11] - SHIELD [pin 10] - VDD [pin 4] - VSS [pin 6] ### J2 — [USB-C Receptacle USB2.0](https://www.flux.ai/jharwinbarrozo/usb-c-receptacle-usb20.md) - Manufacturer Name: Amphenol - Datasheet URL: https://media.digikey.com/pdf/Data%20Sheets/Amphenol%20PDFs/12401548E4%232A%20Drawing.pdf - Role: Connector - Role Details: USB Type-C receptacle for power and data - Package: Surface Mount, Right Angle; Through Hole - Manufacturer Part Number: 12401548E4#2A **Pins:** - CC1 [pin A5] - CC2 [pin B5] - D- [pin B7] - D- [pin A7] - D+ [pin B6] - D+ [pin A6] - GND [pin A12] - GND [pin A1] - GND [pin B12] - SBU1 [pin A8] - SBU2 [pin B8] - SHIELD [pin SH1] - VBUS [pin B4] - VBUS [pin A4] ### SW1 — [Tactile Switch SPST-NO](https://www.flux.ai/collinsemasi/tactile-switch-spst-no.md) - Role: Debouncing - Manufacturer Part Number: PTS526 SK15 SMTR2 LFS - Manufacturer Name: C&K - Datasheet URL: https://www.ckswitches.com/media/2780/pts526.pdf - Role Details: Pushbutton for user control **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] - 4 [pin 4] ### U1 — [ESP32-S3-WROOM-1-N16R8](https://www.flux.ai/alantyger/esp32-s3-wroom-1-n16r8.md) - Manufacturer Name: Espressif Systems - Purchase Url: https://octopart.com/esp32-s3-wroom-1-n16r8-espressif+systems-124180817?r=spc#CadModels - Role Details: Central MCU for audio processing and Wi-Fi connectivity - Part Type: Microcontroller - Manufacturer Part Number: ESP32-S3-WROOM-1-N16R8 - Datasheet URL: https://www.espressif.com/sites/default/files/documentation/esp32-s3-wroom-1_wroom-1u_datasheet_en.pdfhttps://www.espressif.com/sites/default/files/documentation/esp32-s3-wroom-1_wroom-1u_datasheet_en.pdf - Role: Microcontroller **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 — [INMP441](https://www.flux.ai/vasyl/inmp441.md) - Role Details: I2S MEMS microphone for audio input to ESP32-S3 - Part Type: Microphone - Role: Sensor - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: INMP441 - Manufacturer Name: TDK InvenSense - Datasheet URL: https://invensense.tdk.com/wp-content/uploads/2015/02/INMP441.pdf?ref_disty=digikey **Pins:** - GND [pin 1] - L/R [pin 4] - SCK [pin 6] - SD [pin 3] - VDD [pin 2] - WS [pin 5] ### U3 — [LM3671MF-3.3/NOPB](https://www.flux.ai/adrian95/lm3671mf-33nopb.md) - Part Type: Integrated Circuit - Package: SC-74A - Datasheet URL: https://www.ti.com/general/docs/suppproductinfo.tsp?distId=10&gotoUrl=https%3A%2F%2Fwww.ti.com%2Flit%2Fgpn%2Flm3671 - Role: Power Management - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: LM3671MF-3.3/NOPB - Role Details: 5V to 3.3V buck regulator powering ESP32-S3 and peripherals - Manufacturer Name: Texas Instruments **Pins:** - EN [pin 3] - FB [pin 4] - GND [pin 2] - SW [pin 5] - VIN [pin 1] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/mani6ue/random-chocolate-r2-d2](https://www.flux.ai/mani6ue/random-chocolate-r2-d2).* --- *Generated from [https://www.flux.ai/mani6ue/random-chocolate-r2-d2](https://www.flux.ai/mani6ue/random-chocolate-r2-d2)*