# NorrWatch v1
## Description
Exposed bare PCB smartwatch with ESP32-C3, MAX30102, IP5306 charging, microSD, haptic motor, USB-C, and 40 mm round 2-layer layout for JLCPCB BASIC assembly.
## Project Details
- **Owner:** el4swastaken
- **Created:** 3/18/2026
- **Last Updated:** 3/18/2026
- **Visibility:** Public
- **Software:** NorrOS
- **Layer Count:** 2
- **Connectivity:** WiFi BLE USB I2C SPI microSD
- **Power Requirements:** USB-C 5V input, single-cell 120 mAh LiPo, on-board charger/power-path, 3.3V system rail
- **Manufacturing Quantity Target:** 5
- **System Architecture:** ```mermaid
flowchart TD
USB["USB-C 5V Input"] --> CHG["IP5306 Charger Power Path"]
BAT["120mAh LiPo JST PH2.0"] --> CHG
CHG --> LDO["AMS1117 3.3V LDO"]
LDO --> MCU["ESP32-C3-WROOM-02U-N4"]
LDO --> HR["MAX30102 HR SpO2 Sensor"]
LDO --> SD["TF PUSH microSD"]
LDO --> HAPTIC["Coin Vibration Motor"]
BTN1["BOOT Button GPIO0"] --> MCU
BTN2["USER Button GPIO2"] --> MCU
HR -->|I2C SDA GPIO8\nI2C SCL GPIO9\nINT GPIO7| MCU
SD -->|SPI| MCU
HAPTIC -->|PWM GPIO3| MCU
USB -->|D+ D- CC1 CC2| MCU
```
- **Board Diameter:** 40 mm
- **Board Shape:** Round
- **Human Interface:** MAX30102 sensor, 2 tactile buttons, coin vibration motor
- **Compliance:** JLCPCB BASIC parts only
- **Target Batch Cost:** 120 SEK / 5 pcs
## Key Components
### Card1 — [TF PUSH](https://www.flux.ai/lcsc/tf-push.md)
- Role: microSD Connector
- Connector Gender: Non-Gendered
- Manufacturer Part Number: TF PUSH
- Package: TF-SMD_TF-PUSH
- Manufacturer Name: SHOU HAN(首韩)
- Connector Rows: 1
- Product Info Url: https://lcsc.com/product-detail/Connector-Card-Sockets_SHOU-HAN-SHOU-HAN-TFDeck-TF-Deck_C393941.html
- Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/1912111437_SHOU-HAN-TF-PUSH_C393941.pdf
- Role Details: Right-edge removable TF/microSD socket for SPI storage
- Package or Case Code: TF-SMD_TF-PUSH
- Connector Type: Memory Connectors
- LCSC Part Number: C393941
- Part Type: SIM Card Connectors
- JLCPCB Part Class: Extended Part
- Connector Pitch: 2.54mm
- Connector Positions: 9
**Pins:**
- 10 [pin 10]
- 11 [pin 11]
- 12 [pin 12]
- 13 [pin 13]
- CD [pin 9]
- CD/DAT3 [pin 2]
- CLX [pin 5]
- CMD [pin 3]
- DAT0 [pin 7]
- DAT1 [pin 8]
- DAT2 [pin 1]
- VDD [pin 4]
- VSS [pin 6]
### CN1 — [S2B-PH-SM4-TB(LF)(SN)](https://www.flux.ai/lcsc/s2b-ph-sm4-tblfsn.md)
- Part Type: Wire To Board / Wire To Wire Connector
- Connector Gender: Female
- JLCPCB Part Class: Extended Part
- Package: CONN-SMD_P2.00_S2B-PH-SM4-TB-LF-SN
- LCSC Part Number: C295747
- Connector Pitch: 2mm
- Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2102031704_JST-S2B-PH-SM4-TB-LF-SN_C295747.pdf
- Connector Rows: 1
- Manufacturer Part Number: S2B-PH-SM4-TB(LF)(SN)
- Connector Positions: 2
- Manufacturer Name: JST
- Role Details: Pin 1 battery positive, pin 2 battery negative for 1-cell LiPo
- Connector Type: Wire-to-board connector
- Role: Battery Connector
- Product Info Url: https://lcsc.com/product-detail/_JST-Sales-America_S2B-PH-SM4-TB-LF-SN_JST-Sales-America-S2B-PH-SM4-TB-LF-SN_C295747.html
- Package or Case Code: CONN-SMD_P2.00_S2B-PH-SM4-TB-LF-SN
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
- 3 [pin 3]
- 4 [pin 4]
### MOT1 — [LCM1027A2445F](https://www.flux.ai/lcsc/lcm1027a2445f.md)
- LCSC Part Number: C2759984
- Manufacturer Part Number: LCM1027A2445F
- Package or Case Code: VIBRATING-MOTOR-SMD_WELDING
- Package: VIBRATING-MOTOR-SMD_WELDING
- Part Type: Micro Motor & Motor
- JLCPCB Part Class: Extended Part
- Role: Vibration Motor
- Role Details: Battery-powered haptic actuator switched by Q1
- Manufacturer Name: LEADER(立得)
**Pins:**
- - [pin 1]
- + [pin 2]
### Q1 — [S8050](https://www.flux.ai/adrian95/s8050.md)
- Manufacturer Part Number: S8050
- Package: SOT-23
- Part Type: Transistor
- Role Details: Low-side NPN switch for vibration motor from GPIO3 PWM
- Role: Motor Driver
- Datasheet URL: https://pdf1.alldatasheet.com/datasheet-pdf/view/33773/WINGS/S8050.html
- Manufacturer Name: MDD
- License: https://creativecommons.org/licenses/by/4.0/
**Pins:**
- B [pin 1]
- C [pin 3]
- E [pin 2]
### SW1 — [SW_Push](https://www.flux.ai/adrian95/swpush.md)
- Datasheet URL: https://us.schurter.com/en/datasheet/typ_6x6_mm_tact_switches.pdf
- Role Details: ESP32-C3 GPIO0 boot/flash button to ground
- Role: Boot Button
- Manufacturer Part Number: 1301.9314
- Package: SMD
- Manufacturer Name: Schurter Inc.
- Part Type: Switch
**Pins:**
- 1
- 2
### SW2 — [SW_Push](https://www.flux.ai/adrian95/swpush.md)
- Role: User Button
- Manufacturer Part Number: 1301.9314
- Role Details: User input button on GPIO2 to ground
- Package: SMD
- Datasheet URL: https://us.schurter.com/en/datasheet/typ_6x6_mm_tact_switches.pdf
- Manufacturer Name: Schurter Inc.
- Part Type: Switch
**Pins:**
- 1
- 2
### U1 — [ESP32-C3-WROOM-02U-N4](https://www.flux.ai/lcsc/esp32-c3-wroom-02u-n4.md)
- Manufacturer Name: ESPRESSIF(乐鑫)
- Package or Case Code: WIFI-SMD_L18.0-W14.3_ESP32-C3-WROOM-02U-N4
- JLCPCB Part Class: Extended Part
- LCSC Part Number: C2926676
- Manufacturer Part Number: ESP32-C3-WROOM-02U-N4
- Role: MCU
- Package: WIFI-SMD_L18.0-W14.3_ESP32-C3-WROOM-02U-N4
- Role Details: Main ESP32-C3 WiFi/BLE controller with external antenna connector
**Pins:**
- 3V3 [pin 1]
- EN [pin 2]
- GND [pin 21]
- GND [pin 23]
- GND [pin 24]
- GND [pin 19]
- GND [pin 9]
- GND [pin 26]
- GND [pin 22]
- GND [pin 25]
- GND [pin 27]
- GND [pin 20]
- IO0 [pin 18]
- IO1 [pin 17]
- IO10 [pin 10]
- IO18 [pin 13]
- IO19 [pin 14]
- IO2 [pin 16]
- IO3 [pin 15]
- IO4 [pin 3]
- IO5 [pin 4]
- IO6 [pin 5]
- IO7 [pin 6]
- IO8 [pin 7]
- IO9 [pin 8]
- RXD [pin 11]
- TXD [pin 12]
### U2 — [MAX30102EFD+T](https://www.flux.ai/vasy_skral/max30102efdplust.md)
- Part Type: Integrated Circuit
- Manufacturer Part Number: MAX30102EFD+T
- Role Details: Heart-rate and SpO2 optical sensor on I2C
- Symbol Style: Parametric
- Manufacturer Name: Maxim Integrated
- Package: Oximeter/Heart Rate Sensor
- Datasheet URL: https://datasheets.maximintegrated.com/en/ds/MAX30102.pdf
- License: https://creativecommons.org/licenses/by/4.0/
- Role: Sensor
**Pins:**
- ~INT [pin 13]
- GND [pin 12]
- IR_DRV [pin 6]
- NC [pin 8]
- NC [pin 14]
- NC [pin 1]
- NC [pin 7]
- PGND [pin 4]
- R_DRV [pin 5]
- SCL [pin 2]
- SDA [pin 3]
- VDD [pin 11]
- VLED+ [pin 10]
- VLED+ [pin 9]
### U3 — [IP5306](https://www.flux.ai/lcsc/ip5306.md)
- Part Type: Battery Management ICs
- Manufacturer Name: INJOINIC(英集芯)
- Max Current: 2.4A
- Package or Case Code: ESOP-8_L4.9-W3.9-P1.27-LS6.0-BL-EP
- LCSC Part Number: C181692
- JLCPCB Part Class: Extended Part
- Datasheet URL: https://www.lcsc.com/datasheet/lcsc_datasheet_2304140030_INJOINIC-IP5306_C181692.pdf
- Max Output Voltage: 5V
- Product Info Url: https://lcsc.com/product-detail/PMIC-Battery-Management_IP5306_C181692.html
- Max Input Voltage: 5V
- Role Details: Single-cell LiPo charger and power-path controller from USB input
- Role: Charger/Power Path
- Package: ESOP-8_L4.9-W3.9-P1.27-LS6.0-BL-EP
- Manufacturer Part Number: IP5306
**Pins:**
- BAT [pin 6]
- EP [pin 9]
- KEY [pin 5]
- LED1 [pin 2]
- LED2 [pin 3]
- LED3 [pin 4]
- SW [pin 7]
- VIN [pin 1]
- VOUT [pin 8]
### U4 — [AMS1117-3.3](https://www.flux.ai/vasy_skral/ams1117-33.md)
- Datasheet URL: http://www.advanced-monolithic.com/pdf/ds1117.pdf
- Manufacturer Name: AMS
- Symbol Style: Parametric
- Role: Regulator
- Role Details: 3.3V LDO for ESP32, sensor and SD rail
- Part Type: Integrated Circuit
- Package: SOT-223
- License: https://creativecommons.org/licenses/by/4.0/
- Manufacturer Part Number: AMS1117-3.3
**Pins:**
- GND [pin 1]
- TAB(VOUT) [pin 4]
- VIN [pin 3]
- VOUT [pin 2]
### USB1 — [TYPE-C16PIN](https://www.flux.ai/lcsc/type-c16pin.md)
- Product Info Url: https://lcsc.com/product-detail/USB-Connectors_SHOU-HAN-TYPE-C16PIN_C393939.html
- Package or Case Code: USB-C-SMD_TYPE-C16PIN
- LCSC Part Number: C393939
- Role Details: USB-C receptacle for 5V sink power and USB D+/D- flashing connection
- Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/1912111437_SHOU-HAN-TYPE-C16PIN_C393939.pdf
- JLCPCB Part Class: Extended Part
- Manufacturer Part Number: TYPE-C16PIN
- Part Type: USB Connectors
- Manufacturer Name: SHOU HAN(首韩)
- Package: USB-C-SMD_TYPE-C16PIN
- Role: USB-C Connector
**Pins:**
- CC1 [pin A5]
- CC2 [pin B5]
- DN1 [pin A7]
- DN2 [pin B7]
- DP1 [pin A6]
- DP2 [pin B6]
- GND [pin A1B12]
- GND [pin B1A12]
- SBU1 [pin A8]
- SBU2 [pin B8]
- SHELL [pin 4]
- SHELL [pin 1]
- SHELL [pin 3]
- SHELL [pin 2]
- VBUS [pin A4B9]
- VBUS [pin B4A9]
*The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/el4swastaken/norrwatch-v1](https://www.flux.ai/el4swastaken/norrwatch-v1).*
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