# Chemical Coffee Dejarik ## Description Welcome to your new project. Imagine what you can build here. ## Project Details - **Owner:** bektaiyr - **Created:** 2/11/2026 - **Last Updated:** 2/11/2026 - **Visibility:** Public - **System Architecture:** flowchart TD subgraph Power BAT1[Cell 1 18650] BAT2[Cell 2 18650] BMS[2S BMS] VBAT[VBAT rail] GNDN[GND] end subgraph MCU ESP[ESP32 WROOM 32U] end subgraph Sensors MPU1[MPU6050 1] MPU2[MPU6050 2] VSENSE[Battery voltage sense] end subgraph Radio LORA[SX1278] end BAT1 --> BAT2 BAT2 --> BMS BMS --> VBAT BMS --> GNDN VBAT --> VSENSE VSENSE --> ESP ESP -->|I2C SDA/SCL| MPU1 ESP -->|I2C SDA/SCL| MPU2 ESP -->|SPI MOSI/MISO/SCK/CS| LORA VBAT --> ESP GNDN --> ESP GNDN --> MPU1 GNDN --> MPU2 GNDN --> LORA VBAT --> LORA ## Key Components ### BT1 — [BH-18650-B1BA002](https://www.flux.ai/lcsc/bh-18650-b1ba002.md) - Manufacturer Part Number: BH-18650-B1BA002 - Role: Energy Storage - Battery Type: 18650 - Package: BatteryHolder - Operating Temperature: -25°C ~ +80°C - Part Type: Battery Connectors - Connector Type: Battery box - JLCPCB Part Class: Extended Part - LCSC Part Number: C2988620 - Role Details: Cell1 (lower cell). Pin1=B- (pack negative), Pin2=BM (midpoint). - Manufacturer Name: MYOUNG(美阳) - Package or Case Code: BATTERY-SMD_18650-1S-L77.1-W20.7-1 **Pins:** - 1 [pin 1] - 2 [pin 2] ### BT2 — [BH-18650-B1BA002](https://www.flux.ai/lcsc/bh-18650-b1ba002.md) - Operating Temperature: -25°C ~ +80°C - Part Type: Battery Connectors - LCSC Part Number: C2988620 - JLCPCB Part Class: Extended Part - Connector Type: Battery box - Package: BatteryHolder - Manufacturer Name: MYOUNG(美阳) - Package or Case Code: BATTERY-SMD_18650-1S-L77.1-W20.7-1 - Manufacturer Part Number: BH-18650-B1BA002 - Battery Type: 18650 - Role Details: Cell2 (upper cell). Pin1=BM (midpoint), Pin2=B+ (pack positive). - Role: Energy Storage **Pins:** - 1 [pin 1] - 2 [pin 2] ### CN1 — [B2B-PH-K-S(LF)(SN)](https://www.flux.ai/lcsc/b2b-ph-k-slfsn.md) - JLCPCB Part Class: Extended Part - Connector Gender: Male - Manufacturer Part Number: B2B-PH-K-S(LF)(SN) - Product Info Url: https://lcsc.com/product-detail/PH-Connectors_JST_B2B-PH-K-S-LF-SN_B2B-PH-K-S-LF-SN_C131337.html - Role: Connector - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2304140030_JST-B2B-PH-K-S-LF-SN_C131337.pdf - Connector Type: Wire To Board Connector - Connector Pitch: 2mm - Connector Rows: 1 - Package or Case Code: CONN-TH_B2B-PH-K-S - Package: THT - LCSC Part Number: C131337 - Connector Positions: 2 - Manufacturer Name: JST - Part Type: Wire To Board / Wire To Wire Connector - Role Details: Battery pack output connector exposing VBAT and GND. **Pins:** - 1 [pin 1] - 2 [pin 2] ### HMC5883L1 — [HMC5883L](https://www.flux.ai/electech/hmc5883l.md) - Package: Module - Manufacturer Part Number: 29133 - Part Type: Module - Role: Sensor - Manufacturer Name: Digi-Key - Role Details: HMC5883L compass module (HW-127/GY-127 style) on ESP32 I2C bus. **Pins:** - 3.3V - DRDY [pin 5] - GND [pin 2] - SCL [pin 3] - SDA [pin 4] - VIN [pin 1] ### J1 — [Pin Header 01x08 2.54mm Vertical](https://www.flux.ai/adrian95/pin-header-01x08-254mm-vertical.md) - Package: THT - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Connector - Role Details: GPIO breakout header to label SPI/I2C/ADC pins. - Role: Connector **Pins:** - 1 [pin 1] - 2 [pin 2] - 3 [pin 3] - 4 [pin 4] - 5 [pin 5] - 6 [pin 6] - 7 [pin 7] - 8 [pin 8] ### J2 — [Pin Header 01x04 2.54mm](https://www.flux.ai/vasyl/pin-header-01x04-254mm.md) - Role: Connector - Part Type: Connector - Package: THT - Role Details: Module pin headers for I2C sensor and voltage sense. **Pins:** - Pin_1 - Pin_2 - Pin_3 - Pin_4 ### J3 — [Pin Header 01x04 2.54mm](https://www.flux.ai/vasyl/pin-header-01x04-254mm.md) - Role: Connector - Part Type: Connector - Package: THT - Role Details: Module pin headers for I2C sensor and voltage sense. **Pins:** - Pin_1 - Pin_2 - Pin_3 - Pin_4 ### J4 — [Pin Header 01x04 2.54mm](https://www.flux.ai/vasyl/pin-header-01x04-254mm.md) - Package: THT - Part Type: Connector - Role Details: 4-wire 2S BMS interface header. Pin_1=B-, Pin_2=P-, Pin_3=P+, Pin_4=B+. - Role: Connector **Pins:** - Pin_1 - Pin_2 - Pin_3 - Pin_4 ### J5 — [Pin Header 01x04 2.54mm](https://www.flux.ai/vasyl/pin-header-01x04-254mm.md) - Part Type: Connector - Role Details: Placeholder header for 2S 3A BMS module terminals (B+, BM, B-, P-). - Role: Connector - Package: THT **Pins:** - Pin_1 - Pin_2 - Pin_3 - Pin_4 ### U2 — [SX1278](https://www.flux.ai/kicad-part-library/sx1278.md) - Datasheet URL: https://semtech.my.salesforce.com/sfc/p/#E0000000JelG/a/2R0000001Rbr/6EfVZUorrpoKFfvaF_Fkpgp5kzjiNyiAbqcpqh9qSjE - Manufacturer Part Number: SX1278 - Package or Case Code: QFN-28-1EP_6x6mm_P0.65mm_EP4.8x4.8mm **Pins:** - ~{RESET} [pin 7] - DIO0 [pin 8] - DIO1 [pin 9] - DIO2 [pin 10] - DIO3 [pin 11] - DIO4 [pin 12] - DIO5 [pin 13] - GND [pin 21] - GND [pin 29] - GND [pin 23] - GND [pin 26] - GND [pin 22] - GND [pin 15] - MISO [pin 17] - MOSI [pin 18] - NSS [pin 19] - PA_BOOST [pin 27] - RFI_LF [pin 1] - RFO_LF [pin 28] - RXTX/RF_MOD [pin 20] - SCK [pin 16] - VBAT_ANA [pin 3] - VBAT_DIG [pin 14] - VBAT_RF [pin 24] - VR_ANA [pin 2] - VR_DIG [pin 4] - VR_PA [pin 25] - XTA [pin 5] - XTB [pin 6] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/bektaiyr/chemical-coffee-dejarik](https://www.flux.ai/bektaiyr/chemical-coffee-dejarik).* --- *Generated from [https://www.flux.ai/bektaiyr/chemical-coffee-dejarik](https://www.flux.ai/bektaiyr/chemical-coffee-dejarik)*