This slide will focus a bit more on μ’, the inductive value, also called real part of permeability. KEMET has developed two series that specifically focus on reaching a large μ’ value while keeping the magnetic loss μ’’ as low as possible in the carrier frequency 13.56 MHz, which is commonly used for RFID. The graph on the right side illustrates that having a small μ’’ is going to be as important as having a large μ’ in the targeted frequency range in order to have the best efficiency. The M4 series was released later, allowing the operating temperature range to go up to +105°C, and is also available in roll packaging. The RM4A series also remains of interest, as its higher permeability reaches 50 μ’, compared to the 40 μ’ of the M4 series. Playing on the thickness of the products will then help to fine-tune and select the most suitable part according to the requirements of the application.