MCP9600 | GUILCOR SENSORS

MCP9600
Temperature sensors

Thermocouple-to-digital converter with I²C output, enabling accurate temperature measurement in industrial environments.

Maximum precision
+/- 1,5°K

Measurement range
-200 / 1800°C

Resolution
18 bits

Power supply voltage
2,7 →5,5V

Sampling rate

0,063 to 8Hz

I2C adress
0 x 60

Typical current
200µA(active)

Price
High

What is a MCP9600 sensor ?

The MCP9600 is a digital amplifier for thermocouples, featuring an 18-bit converter and integrated cold junction compensation.

It allows for the direct connection of a thermocouple to a microcontroller via I²C, without the need for a complex analog chain (amplifier, compensation, ADC…).

In practice, it transforms a millivolt signal (from the thermocouple) into a calibrated digital temperature value, ready to be read by an Arduino, ESP32, STM32, Raspberry Pi, etc.

Operating principle

The MCP9600 measures the voltage generated by the thermocouple (Seebeck effect) and then converts it into temperature using a transfer equation specific to the chosen type.

It also measures the internal reference temperature (cold junction) using an integrated sensor, and then automatically performs the compensation.

T_mesurée = T_thermocouple + T_référence interne

💡 All the linearization, compensation, and conversion calculations are performed by the MCP9600 — no external equations are required.

Principle diagram (I2C connection)

+3.3V
 │
[MCP9600]
 │ SDA ─────────┐
 │ SCL ─────────┤── [I²C Microcontroller]
 │ GND          │
 │ TH+ / TH− ───┘── (Thermocouple)

💡 Just connect the thermocouple directly to the TH+ and TH− pins.

Compatible thermocouple types and ranges

Type	Typical range temperature (°C)	Sensitivity (µV/°C)
K	−200 → +1 372	41
J	−210 → +1 200	55
T	−250 → +400	43
N	−200 → +1 300	39
S	0 → +1 760	10
E	−200 → +1 000	61
B	600 → +1 820	10
R	0 → +1 760	10

💡 The accuracy mainly depends on the type and stability of the thermocouple used.

Application areas

⚙️ Industrial furnace monitoring

🧪 Laboratory instrumentation

🔬 Embedded thermocouples (3D printing, robots, melting)

⚡ Portable measuring devices (industrial IoT)

Should I choose a MCP9600 sensor ?

Strengths points

🧩 All-in-one digital
→ Replace amplifier, cold reference, and ADC, no external components required.
🧠 Multi-type compatibility
→ One component for all standard thermocouples (B, E, J, K, N, R, S, T).
🎯 Compensation and internal linearization
→ Reliable accuracy without complex software processing.

Weaknesses points

🌡️ Depends on the accuracy of the external thermocouple
→ The MCP9600 is accurate, but it cannot correct a worn or poorly calibrated sensor.
⚙️ Temperature range limited by internal cold weld
→ If the reference exceeds 85 °C, the compensation becomes inaccurate.
📡 Low sampling rate
→ Max 8 Hz, insufficient for ultra-fast or dynamic measurements.

Useful information

Here is some useful information regarding the MCP9600 sensors.

Main registers (7-bit address: 0x60 → 0x67)

Adress	Registry Name	Function
0x00	Hot Junction Temperature	Thermocouple temperature
0x01	Junction Delta Temperature	Hot/cold difference
0x02	Cold Junction Temperature	Reference internal temperature
0x03	Raw ADC Data	Thermocouple raw tension
0x04	Status Register	Indicate alerts and conversions
0x05	Sensor Configuration	Type of thermocouple, filter, conversion
0x06	Device Configuration	Continuous mode or standby
0x08 → 0x0B	Alert Configuration / Limit	Configurable alert thresholds

I²C Reading Example (pseudo-code)

i2c_start();
i2c_write(0x60 << 1);       // MCP9600 Address
i2c_write(0x00);            // Thermocouple temperature log
i2c_start();
i2c_write((0x60 << 1) | 1); // Lecture
MSB = i2c_read_ack();
LSB = i2c_read_nack();
i2c_stop();

raw = (MSB << 8) | LSB;
temp = raw / 16.0; // Chaque LSB = 0.0625°C

✅ Example:

MSB = 0x0C, LSB = 0x90 →

Temperature = (0x0C90 / 16) = 200.0 °C

Typical integration diagram

Thermocouple
  │
  ├── TH+
  └── TH−
      │
     [MCP9600]
      │ SDA ───────┐
      │ SCL ───────┤── MCU I²C (Arduino, ESP32, STM32…)
      │ GND
      │ VCC (3.3–5V)

💡 Provide pull-up resistors of 4.7 kΩ on SDA/SCL and a clean routing of the TH+ / TH− inputs.

Example configuration (register 0x05 – Sensor Config)

Bit	Name	Description
[7:5]	Type of thermocouple	000=K, 001=J, 010=T, 011=N, 100=S, 101=E, 110=B, 111=R
[4:2]	Digital filter	000 = aucun / 111 = maximum
[1:0]	ADC Resolution	00=0,0625°C / 01=0,125°C / 10=0,25°C / 11=0,5°C

Application Example – Complete Measurement

Selection of thermocouple type in register 0x05
→ 0b000 for type K
Reading register 0x00 (hot junction)
→ Temp_ch = 350,25 °C
Reading register 0x02 (cold solder)
→ Temp_ref = 24,75 °C
Final result:
Tmesureˊe=350,25+24,75=375,0°CT_{\text{mesurée}} = 350,25 + 24,75 = 375,0 °CTmesureˊe=350,25+24,75=375,0°C

✅ Final temperature: 375.0 °C