TDK Electronics · TDK Europe


October 6, 2016

Compact Z transponder coils for automotive applications

  • Dimensions of only 7.7 mm x 7.4 mm x 2.65 mm
  • Qualified to AEC-Q200
  • High sensitivity

TDK Corporation presents a new series of EPCOS z-axis transponder coils for passive entry, passive start (PEPS) car access systems. With their dimensions of just 7.7 mm x 7.4 mm x 2.65 mm the components are extremely compact and feature a very low insertion height. The B82451L*E402 series comprises seven transponder coils covering an inductance range from 1.0 mH to 10.0 mH. Depending on the type, the transponder coils feature a sensitivity of between 7 mV/µT and 23 mV/µT at 125 kHz. The Q factor of the new components is between 50 and 58.

The injection-molded plastic baseplate and laser-welded connections of the winding ensure that the Z transponder coils are extremely robust. The new components are also qualified according to AEC-Q200. 

Moreover, the Z transponder coils can be combined very well with the EPCOS B82450A*A* and B82450A*E* transponder coil series for the x- and y-axes. With their footprints of just 11.4 mm x 3.5 mm and 8 mm x 2.7 mm, respectively, these components are also very compact. Solutions using three discrete transponder coils offer high flexibility of design and can save space on the PCB. A design combining the new Z transponder coil with two 8-mm X and Y transponder coils, for example, needs an area of just 100 mm². All EPCOS transponder coils are RoHS compatible.

Main applications

  • Passive entry, passive start (PEPS) car access systems

Main features and benefits

  • High sensitivity
  • Qualified according to AEC-Q200
  • RoHS compatible

Key data

SeriesDimensions [mm]Inductance [mH]Sensitivity [mV/µT]Q factor
B82451L*E4027.7 x 7.4 x 2.651.0 to 107 to 23 50 to 58