Designed to work with mqtt.chem.wisc.edu.
This is an open source hardware project licensed under the CERN Open Hardware Licence Version 2 - Permissive. Please see the LICENSE file for the complete license.
This PCB was designed using KiCAD version 7.
Refer to mqtt_particle_sensor.pdf for schematic.
PCB images generated with tracespace follow.
| reference | value | manufacturer | part number | price | vendors |
|---|---|---|---|---|---|
| C1 | 1u | Multicomp | MC1206B105K500CT | $0.10 | Newark |
| C2 | 1u | Multicomp | MC1206B105K500CT | $0.10 | Newark |
| C3 | 100u | Illinois Capacitor | 107KXM025M | $0.25 | Newark |
| C4 | 10u | Yageo | CC1206KKX7R8BB106 | $0.25 | Newark |
| C5 | 22u | Murata Electronics | GRM31CC71C226ME11L | $0.75 | Newark |
| R1 | 470k | 1206 1/4 1% | |||
| R2 | 1M | 1206 1/4 1% | |||
| R3 | 1M | 1206 1/4 1% | |||
| R4 | 4.7k | 1206 1/4 1% | |||
| R5 | 4.7k | 1206 1/4 1% | |||
| R6 | 1k | 1206 1/4 1% | |||
| R7 | 1k | 1206 1/4 1% | |||
| R8 | 4.7k | 1206 1/4 1% | |||
| R9 | 4.7k | 1206 1/4 1% | |||
| A1 | ESP8266 HUZZAH BREAKOUT BOARD | Adafruit | 2471 | $10.00 | Newark |
| U1 | Auto Reset Timer | Nexperia | HEF4060BT,653 | $0.50 | Newark |
| U2 | ATtiny85 | Microchip Technology | ATTINY85-20PU | $3.00 | Newark |
| U2 | 8pin Dip Socket | Millmax | 110-93-308-41-001000 | $1.00 | Newark |
| U3 | HPM Particle Sensor | Honeywell | HPMA115S0-XXX | $63.75 | Newark |
| U3 | Header Connector | Molex | 53047-0810 | $0.14 | Newark |
| U3 | 8pin ribbon cable | Molex | 151340801 | $10.06 | Newark |
| D1 | LED (red) | Lite-On Inc. | LTST-C230KRKT | $0.25 | Digikey |
| D2 | LED (green) | Lite-On Inc | LTST-C150KGKT | $0.25 | Digikey |
| PS1 | Power | CUI | VXO7805-500-M-TR | $3.00 | Newark |
| J2 | Barrel Jack | CUI | PJ-002A | $1.00 | Digikey |
| Q1 | 2N7000 | Diodes Inc. | 2N7002K-7 | $0.25 | Newark |
| Q2 | 2N7000 | Diodes Inc. | 2N7002K-7 | $0.25 | Newark |
This project uses micropython, specifically microhomie. Refer to the "firmware" directory in this repository for detailed instructions.