Integrated Electronics Piezo-Electric

IEPE is a set of initials for “Integrated Electronic Piezo Electric”. It is a standard for electronics in transducers (like accelerometers and microphones) that have built-in amplifiers.


ICP is short for “Integrated Circuit-Piezoelectric”. ICP is a trademark name of PCB Corporation for their proprietary implementation of IEPE.


Other trademark names of IEPE from different companies include CCLD, IsoTron or DeltaTron.

Most IEPE sensors work at a constant current between 2 and 20 mA. A common value is 4 mA.

Supplying the IEPE sensor with constant current, results in a positive bias voltage, typically between 8 and 12 Volts, at the output.

The supply or compliance voltage of the constant current source should be 24 to 30 V which is about two times the bias voltage.

Compliance Voltage example calculation

Example sensor specifications:

Sensitivity10 mV/g
Range500 g
Constant Current Excitation2 .. 20 mA
Excitation - Compliance Voltage 18 .. 30 Vdc
Bias Voltage7 .. 12 Vdc

SIRIUS ACC module specifications:

IEPE mode
Excitation2, 4, 8, 12, 16 or 20 mA
Compliance Voltage25 V

Excitation - Compliance Voltage minimum required = 500 g * 10 mV / g +12 V = 17 V

This (17 V) is within the compliance voltage of the SIRIUS ACC amplifier specifications.

Jernej Kovačič, 13.05.2020