TDK Corporation presents a 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 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 these 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 and are qualified according to AEC-Q200.

The Z transponder coils can be combined very well with the EPCOS B82450A transponder coil series for the x- and y-axis. 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 Z transponder coil with two 8 mm X and Y transponder coils for example, needs an area of just 100 mm².