# insole_master_right ## Description Bilateral smart running insole data logger using two nearly identical ESP32-S3 pressure-sensing PCBs. Left variant is an ESP-NOW slave without microSD; right variant is the master with microSD logging. Both preserve the 16-zone FSR mux front end, LiPo charging, AP2112K regulation, USB-C charging input, JST battery connector, and the 280mm x 90mm 2-layer low-profile insole form factor. ## Project Details - **Owner:** tenghis - **Created:** 3/26/2026 - **Last Updated:** 3/28/2026 - **Visibility:** Public - **Stackup:** 2-layer rigid low-profile PCB with bottom ground plane - **System Architecture:** ```mermaid flowchart TD subgraph Left [Left slave variant] LFSR[16-zone FSR array] --> LMUX[CD74HC4067 mux] LMUX --> LMCU[ESP32-S3] LUSB[USB-C charge input] --> LCHG[TP4056 charger] LCHG --> LBAT[LiPo battery] LBAT --> LLDO[AP2112K 3.3V] LLDO --> LMCU LLDO --> LMUX LMCU --> LRADIO[ESP-NOW sender] end subgraph Right [Right master variant] RFSR[16-zone FSR array] --> RMUX[CD74HC4067 mux] RMUX --> RMCU[ESP32-S3] RUSB[USB-C charge input] --> RCHG[TP4056 charger] RCHG --> RBAT[LiPo battery] RBAT --> RLDO[AP2112K 3.3V] RLDO --> RMCU RLDO --> RMUX RMCU --> RSD[microSD logger] LMCU -->|ESP-NOW 16 channels| RMCU end ``` - **Board Thickness Target:** 1.0mm - **Logging Architecture:** Master-only microSD logging at 100Hz to COMBO_LOG.CSV. Slave transmits 16 channels via ESP-NOW to master. - **Board Outline:** 280mm x 90mm insole silhouette, tapered toe and wider heel - **Manufacturing Quantity Target:** Production prototype - **Finish:** ENIG - **Layout Notes:** Use final right-foot insole silhouette, continuous bottom GND fill except ESP32 antenna keepout, and edge-routed outline for thin insole construction. - **Implementation Details:** 280mm x 90mm insole-shaped wearable PCB, 2-layer with solid bottom ground plane, 0.15mm min trace/clearance, 0.6/0.3mm via, 0.5mm board edge clearance, 0.5mm 3V3 traces, 1.0mm battery/VBUS traces, 0.2mm signal traces, ENIG finish, both-side solder mask. - **Variant Strategy:** Two nearly identical PCB variants: left slave without microSD, right master with microSD logging. Both use the exact same ESP32-S3 GPIO assignments for mux control and ADC. IMU and BLE streaming are removed; inter-board transfer is ESP-NOW only. ## Key Components ### J1 — [Type-C-2.0-6Pin](https://www.flux.ai/jharwinbarrozo/type-c-20-6pin.md) - Manufacturer Name: CIKI - Role Details: Power-only USB-C receptacle used as 5V sink with CC pull-downs - Package: SMT Right Angle - Role: USB-C Power Input - Part Type: Connector - Datasheet URL: https://datasheet.lcsc.com/lcsc/2204071830_CIKI-Type-C-2-0-6Pin_C2987385.pdf - Manufacturer Part Number: Type-C-2.0-6Pin **Pins:** - CC1 - CC2 - GND - GND__1 - SHIELD - SHIELD__1 - SHIELD__2 - SHIELD__3 - V-BUS - V-BUS__1 ### J2 — [S2B-PH-SM4-TB(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-sm4-tblfsn.md) - Manufacturer Name: JST Sales America Inc. - Package: Right Angle SMD - Role Details: JST-PH 2-pin LiPo input connector - Manufacturer Part Number: S2B-PH-SM4-TB(LF)(SN) - Role: Battery Connector - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Connector - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf **Pins:** - P1 [pin 1] - P2 [pin 2] ### J3 — [FFC2B28-16-G](https://www.flux.ai/adrian95/ffc2b28-16-g.md) - License: https://creativecommons.org/licenses/by/4.0/ - Package: 0.5mm Right Angle FFC - Datasheet URL: https://gct.co/files/specs/0.5mm-ffc-spec.pdf - Part Type: Connector - Role Details: 16-pin FFC connector for toe-mounted FSR flex tail - Manufacturer Part Number: FFC2B28-16-G - Manufacturer Name: GCT - Role: Sensor Connector **Pins:** - 1 [pin 1] - 10 [pin 10] - 11 [pin 11] - 12 [pin 12] - 13 [pin 13] - 14 [pin 14] - 15 [pin 15] - 16 [pin 16] - 2 [pin 2] - 3 [pin 3] - 4 [pin 4] - 5 [pin 5] - 6 [pin 6] - 7 [pin 7] - 8 [pin 8] - 9 [pin 9] - MP1 [pin MP1] - MP2 [pin MP2] ### U1 — [ESP32-S3-WROOM-1](https://www.flux.ai/kicad-part-library/esp32-s3-wroom-1.md) - Package or Case Code: ESP32-S3-WROOM-1 - Part Type: RF Module - Package: Module - Datasheet URL: https://www.espressif.com/sites/default/files/documentation/esp32-s3-wroom-1_wroom-1u_datasheet_en.pdf - Manufacturer Part Number: ESP32-S3-WROOM-1 - Manufacturer Name: Texas Instruments Inc. - Role: MCU - Role Details: ESP32-S3 MCU for bilateral insole logger. Fixed GPIO map: ADC GPIO11, mux S0 GPIO1, S1 GPIO2, S2 GPIO13, S3 GPIO10, mux EN GPIO14, SD SPI GPIO4/5/6/7, shutdown button GPIO0, UART IO43/IO44. **Pins:** - 3V3 [pin 2] - EN [pin 3] - GND [pin 1] - GND [pin 40] - GND [pin 41] - 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 — [CD74HC4067M](https://www.flux.ai/kicad-part-library/cd74hc4067m.md) - Role: Analog Multiplexer - Manufacturer Name: Texas Instruments Inc. - Package or Case Code: SOIC-24W_7.5x15.4mm_P1.27mm - Manufacturer Part Number: CD74HC4067M - Role Details: Scans 16 FSR channels into one ESP32 ADC input - Datasheet URL: http://www.ti.com/lit/ds/symlink/cd74hc4067.pdf - Package: SOIC-24 **Pins:** - ~{E} [pin 15] - COM [pin 1] - GND [pin 12] - I0 [pin 9] - I1 [pin 8] - I10 [pin 21] - I11 [pin 20] - I12 [pin 19] - I13 [pin 18] - I14 [pin 17] - I15 [pin 16] - I2 [pin 7] - I3 [pin 6] - I4 [pin 5] - I5 [pin 4] - I6 [pin 3] - I7 [pin 2] - I8 [pin 23] - I9 [pin 22] - S0 [pin 10] - S1 [pin 11] - S2 [pin 14] - S3 [pin 13] - VCC [pin 24] ### U4 — [AP2112K-3.3TRG1](https://www.flux.ai/adrian95/ap2112k-33trg1.md) - Part Type: Integrated Circuit - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: Diodes Incorporated - Manufacturer Part Number: AP2112K-3.3TRG1 - Role: LDO Regulator - Role Details: Provides low-noise 3.3V rail for ESP32, IMU, and mux - Datasheet URL: https://www.diodes.com/assets/Datasheets/AP2112.pdf - Package: SOT-23-5 **Pins:** - EN [pin 3] - GND [pin 2] - NC [pin 4] - VIN [pin 1] - VOUT [pin 5] ### U5 — [TP4056](https://www.flux.ai/vasy_skral/tp4056.md) - Datasheet URL: https://dlnmh9ip6v2uc.cloudfront.net/datasheets/Prototyping/TP4056.pdf - Package: SOP-8 - Role: Battery Charger - Manufacturer Name: NanJing Top Power ASIC Corp. - Part Type: Integrated Circuit - Role Details: Linear LiPo charger for USB-C 5V input at heel section - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: TP4056 **Pins:** - ~CHRG [pin 7] - ~STDBY [pin 6] - BAT [pin 5] - CE [pin 8] - EP [pin 9] - GND [pin 3] - PROG [pin 2] - TEMP [pin 1] - VCC [pin 4] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/tenghis/insolemasterright](https://www.flux.ai/tenghis/insolemasterright).* --- *Generated from [https://www.flux.ai/tenghis/insolemasterright](https://www.flux.ai/tenghis/insolemasterright)*