ET-S59
MAX31855 Thermocouple Amplifier
K-type thermocouple reader to 1350 °C, 3.3/5 V SPI
AED 49.00
Out of stockOverview
K-type thermocouple reader to 1350 °C, 3.3/5 V SPI
The ET-S59 is built around the 1 × Analog Devices MAX31855K — K-type, −200…+1350°C, 0.25°C resolution, cold-junction compensated. It talks over Read-only SPI (SCK, SO, CS); 74LVC125A makes it 3.3V and 5V safe and runs from VIN 3.3–5V, onboard AP2112K.
Designed in Dubai by ElectroTrical — the full schematic, BOM and design notes are published below.
Good for
- Kilns and furnaces
- Reflow ovens
- BBQ and smoker monitoring
Key features
What makes it different
Converter
1 × Analog Devices MAX31855K: K-type, −200…+1350°C, 0.25°C resolution, cold-junction compensated
Interface
Read-only SPI (SCK, SO, CS); 74LVC125A makes it 3.3V and 5V safe
Diagnostics
Open-circuit, short-to-GND and short-to-VCC fault bits
Supply
VIN 3.3–5V, onboard AP2112K
Open documentation
Schematic, BOM and layout notes published for every board.
Breadboard friendly
Standard 2.54 mm pitch and M2.5 mounting holes.
Specifications
Technical specifications
| Converter | 1 × Analog Devices MAX31855K: K-type, −200…+1350°C, 0.25°C resolution, cold-junction compensated |
|---|---|
| Interface | Read-only SPI (SCK, SO, CS); 74LVC125A makes it 3.3V and 5V safe |
| Diagnostics | Open-circuit, short-to-GND and short-to-VCC fault bits |
| Supply | VIN 3.3–5V, onboard AP2112K |
| Size | 25.4 × 25.4 mm |
|---|---|
| Mounting | 4 × M2.5 holes, 2.54 mm from each corner |
| Connectors | 6-pin 2.54 mm header · Screw terminal 2P 5.0mm 17A (THT) — Thermocouple T+ / T− |
| Main IC | MAX31855KASA+T (LCSC C52028) |
| Revision | Rev A |
| Libraries | Adafruit_MAX31855, CircuitPython adafruit_max31855, ESPHome max31855 |
|---|
Performance
Range
Pinout
Pin map and connections
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | VIN | Power | 3.3–5V |
| 2 | GND | Ground | Ground |
| 3 | 3V3 | Power | Regulator output |
| 4 | SCK | SPI | SPI clock ≤5MHz |
| 5 | MISO | SPI | SO, 3.3V |
| 6 | CS | SPI | Channel 1, active low |
Mechanical
Dimensions and what's in the box
In the box
- 1 × ET-S59 MAX31855 Thermocouple Amplifier (assembled)
- 1 × 6-pin 2.54 mm male header, unsoldered
Getting started
- Wire the header: VIN, GND, 3V3, SCK, MISO, CS
- Libraries: Adafruit_MAX31855, CircuitPython adafruit_max31855, ESPHome
max31855
Compare
Which thermocouple board?
| MAX31855 Thermocouple Amplifier (this board)This board | ET-S60 Dual MAX31855 Thermocouple | ET-S19 MAX31856 Thermocouple Amplifier | |
|---|---|---|---|
| What it does | K-type thermocouple reader to 1350 °C, 3.3/5 V SPI | Two K-type thermocouple channels on one board | Universal thermocouple interface, K/J/N/R/S/T/E/B |
| Interface | Read-only SPI (SCK, SO, CS); 74LVC125A makes it… | Read-only SPI (SCK, SO, CS); 74LVC125A makes it… | SPI (mode 1/3), up to ~1MHz through the BSS138… |
| Best for | Kilns and furnaces | Two-zone ovens | Kilns, ovens and reflow controllers |
| Price | 49 AED | 89 AED | 59 AED |
Downloads
Documents and design files
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