A non-contact temperature meter made by @souptik-samanta
- Custom 3D-printed Case
- Based on STM32F103C8 microcontroller
- Breakout for many GPIO pins
- USB-C interface
- RTC (Real-Time Clock) capabilities
- Embedded microcontroller; low power consumption
The STMicroelectronics STM32F103C8 is an ARM Cortex-M3 32-bit microcontroller:
- 72MHz
- 64kB Flash, 20kB SRAM
- Internal 8MHz RC + 32kHz LSE
- RTC, Power saving modes
- JTAG + SWD debug
- 3 synchronous serial interfaces
- More powerful and cheaper
- Tough and industrial-grade (like me )
- More GPIOs, fewer passives
- Doesn’t need a bloated dev board like the RP2040 or ATmega
| Item | Cost (USD) |
|---|---|
| 5× PCBs (JLCPCB) | $20 |
| Component parts | $60 |
| Parts shipping | $10 |
| Case shipping (Hack Club) | $10 |
| Total | ~$100 |
| Designator | Footprint | Qty | Value | LCSC Part # | Price ($) | Notes |
|---|---|---|---|---|---|---|
| C1, C2, C3, C4 | 0402 | 4 | 20pF | 0.11 | Total: 49.55 | |
| C10, C6, C7, C8, C9 | 0402 | 5 | 100nF | 0.32 | Shipping: $10 | |
| C11 | 0402 | 1 | 1uF | 0.24 | SO: $58, CSAE: $10 | |
| C12, C13 | 0603 | 2 | 22uF | 3.63 | SO: $70 | |
| C5 | 0603 | 1 | 100nF | 0.25 | PCB Shipping: $20 | |
| C | Charger"1"10ish $ | |||||
| D1, D2, D3 | 0603 | 3 | LED | 0.50 | SO: $100 | |
| FB1 | 0603 | 1 | FerriteBead_Small | 0.70 | And misc costs | |
| J1 | USB_C_Receptacle_GCT_USB4105-xx-A_16P_TopMnt_Horizontal | 1 | USB_C_Receptacle | 0.90 | Note: Price may increase | |
| J2 | PinHeader_1x04_P2.54mm_Vertical | 1 | MLX90614 | 15.00 | ||
| J3 | PinHeader_1x04_P2.54mm_Vertical | 1 | OLED | 3.00 | ||
| OLED-Extra | I2C Display Module | 1 | OLED Display | 2.00 | ||
| J5 | PinSocket_2x10_P2.54mm_Vertical | 1 | Conn_02x10 | 5.00 | Final Total: $98 | |
| R1 | 0402 | 1 | 10K | 0.30 | ||
| R10, R11, R4 | 0402 | 3 | 330 | 0.50 | ||
| R3 | 0402 | 1 | 0 | 1.00 | ||
| R5, R6 | 0402 | 2 | 20R | 0.50 | ||
| R7 | 0402 | 1 | 1.5K | 0.70 | ||
| R8, R9 | 0402 | 2 | 5.1K | 0.90 | ||
| SW1 | SW_TS-1088-AR02016 | 1 | BOOTSEL | 1.00 | ||
| SW2 | SW_TS-1088-AR02016 | 1 | RST | 1.00 | ||
| U1 | LQFP-48_7x7mm_P0.5mm | 1 | STM32F103C8Tx | 8.00 | ||
| U2 | SOT-223-3_TabPin2 | 1 | AMS1117-3.3 | 1.00 | ||
| U3 | SOT-23-6_Handsoldering | 1 | SRV05-4 | 1.00 | ||
| Y1 | Crystal_SMD_3225-4Pin_3.2x2.5mm | 1 | 8MHz | 0.80 | ||
| Y3 | Crystal_SMD_3215-2Pin_3.2x1.5mm | 1 | 32.768 | 1.20 | ||
| battries from burger 5$$ |


