Sensor interface circuit and sensor module

A sensor interface circuit comprising:

• a frequency synchronization circuit connectable to a sensor,
• the frequency synchronization circuit including:
• a reference voltage source configured to generate a reference voltage;
• a current source connected to the reference voltage source, the current source being configured to generate a current by using the reference voltage;
• a voltage difference detection circuit including a first input node connected to the reference voltage source, a second input node connected to the current source, and an output node, one of a voltage received at the first input node and a voltage received at the second input node corresponding to a detection value of the sensor, and the voltage difference detection circuit being configured to generate a control voltage according to a difference between the voltage received at the first input node and the voltage received at the second input node;
• a voltage-controlled oscillation circuit connected to the output node of the voltage difference detection circuit, the voltage-controlled oscillation circuit being configured to generate an oscillation signal according to the control voltage;
• and
• a frequency/impedance conversion circuit connected between the voltage-controlled oscillation circuit and the second input node of the voltage difference detection circuit, the frequency/impedance conversion circuit being configured to convert a frequency of a signal according to the oscillation signal into impedance.