Compact EPCOS SMT transponder coils have been released by TDK. Measuring just 4.5x3.2x3.2mm, the TC1812 has an inductance of 2.38mH and is designed for operation in the Z-axis. The TC1210 coil is available with an inductance value of 1.08mH or 1.34mH, depending on type, and is suitable for operation in either the X- or Y-axis. According to the company, the TC1210 is the world’s smallest transponder coil, measuring just 3.2x2.5x2.2mm.
Thanks to the reduced dimensions, it has also been possible to reduce the mass of the components by about a third compared to the predecessor products. For example, the TC1210 (B82450A1084C000) weighs just 50mg, while the TC1812 (B82451A2384D000) weighs only 120mg. This makes them particularly suitable for tire pressure monitoring systems. These applications demand especially robust, low-mass components due to the high acceleration forces that are encountered. The terminals of the windings are laser-welded and provide high mechanical stability.
The TC1210 coil has a high sensitivity of 3.1mV/µT or 3.5mV/µT, depending on the type, while the TC1812 coil offers a sensitivity of 7.6mV/µT. All transponder coils are designed for a centre frequency of 125kHz, comply with the AEC-Q200 standard and are RoHS-compatible.