Temperature Sensor MAX6698 7-Channel Smart consisting of circuit diagram

The circuit illustrated in the figure involves the MAX6698 maximum temperature sensor, which utilizes three transistors (VT1 to VT3) and three thermistors (RT1 to RT3). An internal reference voltage source is connected through resistors UREF REX1 to REX3, providing power to the thermistors. The voltage drop across each thermistor is supplied to the THER1 to THER3 pins. Suitable temperature transistors include models such as CMPT3904, SST3904, KST3904-TF, SMBT3904, and FMMT3904CT-ND.

The MAX6698 is a maximum temperature sensor designed for precision thermal monitoring. The circuit operates by utilizing three thermistors, which are resistive temperature devices that change resistance based on temperature variations. Each thermistor (RT1, RT2, RT3) is connected to a corresponding transistor (VT1, VT2, VT3) that acts as a switch to control the output based on the temperature readings.

The internal reference voltage is critical for maintaining the accuracy of the temperature sensing. The resistors (REX1, REX2, REX3) connected to the thermistors ensure that the thermistors are powered correctly, allowing them to provide reliable temperature measurements. The voltage drop across each thermistor is monitored and supplied to the THER pins, which are inputs to the MAX6698, enabling it to determine the maximum temperature among the three sensors.

The choice of transistor models (CMPT3904, SST3904, KST3904-TF, SMBT3904, and FMMT3904CT-ND) is essential for ensuring that the circuit can handle the required switching characteristics and power levels. These transistors are known for their low saturation voltage and fast switching capabilities, making them suitable for temperature sensing applications.

In summary, this circuit configuration effectively utilizes the MAX6698 in conjunction with thermistors and transistors to achieve accurate temperature monitoring and control, suitable for various applications where thermal management is critical. Proper selection of components and careful attention to the circuit design will enhance the performance and reliability of the temperature sensing system. Circuit shown in Figure: MAX6698 maximum temperature with three transistors (VT1 ~ VT3) and three thermistors (RT1 ~ RT3). The internal reference voltage source via a resistor UREF REX1 ~ REX3 were given three thermistor power supply, the voltage drop across the thermistor respectively supplied THER1 ~ THER3 pins. Temperature transistor can be used CMPT3904, SST3904, KST3904-TF, SMBT3904, FMMT3904CT-ND models.