This is just a simple implementation of the MCP3208/MCP3008 A/D chip on a Zero footprint.

I added 2 Form "C" 125vac/2amp 250watt relays to make it more useful.

Relays terminated on 3.5mm screw terminals, A/D inputs on 3-pin .1" pin headers.


Analog signal (3v3 max)

Ground (-)

On-board power supply accepts 2.5mm standard Barrel plug, +7.5V < +24V,

Later version includes optional 8-resistor 2k2Ω SIP pullup- for supervisory loop sensors.

Step 1: Get Your Parts Together!

Download a Digi-Key parts list by clicking HERE

Download the CAD file by clicking HERE

Click HERE for an eBay link $2 Esp12-e

Step 2: Clean Your Parts, Insert Parts, Trim Leads, Resin, Solder...and CLEAN!

I chose to make Analog inputs 0-3

into 2k2 pull-up INPUTS,

-for "supervised" alarm inputs, -using 2k2 5-pin SIP resistor network

I included a TMP36 on Analog 7 for on-board temperature input,

Analog 4,5,6 are 3-wire GENERIC sensor inputs (0 to +3 volts).

Step 3: Program It!

Python / MQTT client?


About This Instructable




Bio: C10 Electrical (General) Contractor Lic.#766331 HighTech Electric (Retired) I built custom estates, specializing in high tech, IoT, access controls, security and communications. Now I ... More »
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