Low Frequency Specification & Integrated Circuits

LF Specification

The LF (Low Frequency) spectrum covers the range from 30 kilohertz (kHz) to 300 kHz, but is typically used between 125 and 134.2 kHz for the applications we supply for. These applications include within challenging environments across sectors from manufacturing to oil, gas, aerospace and automotive, along with supply chain applications. 'Hard' LF Products are ideal to protect against damage from dust and mechanical stress, as well as high temperatures and water immersion.

LF radio waves using higher or lower frequency than the 125 to 134.2 kHz we supply are able to diffract over obstacles, such as mountains, due to their long wavelength. This means they can follow the Earth's contours, travelling beyond the horizon. 'Ground wave' is the name given to this propagation mode, and this is the LF band's main mode. Because a ground wave is polarised vertically, monopole antennas are used for their transmission. LF frequency ground waves can offer reception up to 1,200 miles from their transmitting antenna.

LF is used in radio broadcasting (AM radio), as well as in aircraft beacons, navigation systems, weather systems and radio clocks.

Some radio clocks use an LF receiver, and the ground waves used means that the time signals' precision can be kept protected from disruption as a result of varying propagation paths. These radio clocks are often sold as low cost consumer devices. In the military, a large share of the most powerful navies - the British, United States and Russian navies among them - use LF to communicate with submarines.

EM-Marin Low Frequency Integrated Circuits (IC's)

The following EM-Marin integrated circuits (IC) are offered on the LF frequency:

EM4450 / EM4550

Benefits include integrated PLL system, no external quartz required, sleep mode consumption and direct antenna using bridge drivers (typically used for ticketing, prepayment devices, manufacturing automation and high security hands free access control).


Benefits include reader talk first feature, 32 bit unique identifier, 32 bit password read and write protection and lock feature converts EEPROM word in 'read only' (typically used for animal identification, access control, industrial, waste management standard and pigeon races).


Benefits include very low power consumption and high performances, one-chip rectifier and voltage limiter, no external supply buffer capacitor needed and several data rate and data encoding options (typically used for animal identification, access control, anti-counterfeiting, waste management standard, logistics automation and industrial transponder).

NXP Low Frequency Integrated Circuits (IC's)

The following NXP HITAG transponder ICs are offered on the LF frequency:




Benefits of NXP HITAG transponder ICs include strong performance and high reliability. These ICs operate in the 100 to 150 kHz frequency range and are designed to be used in harsh environments. A large variety of applications are supported by the HITAG transponder IC portfolio, and the varieties above offer options of read/write or read-only access, several memory sizes and delivery formats and proprietary encryption.

These HITAG transponder ICs are compliant with the industrial ISO 18000-2 standard, as well as ISO 14223 or ISO 11784/85 animal identification standards. They feature a very low power design, which supports long read ranges for the purpose of livestock tracking.