P9242-R Datasheet

© 2018 Integrated Device Technology, Inc

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January 16, 2018

7.14 LC Resonant Circuit

The LC resonant circuit comprises the series primary resonant coil (LP) and series capacitance (CP). The transmitter coil assembly is vendor

specific, and it must comply with the WPC recommendation. The WPC recommendations include the self-inductance value, DC resistance

(DCR), Q-factor, size, and number of turns.

The P9242-R is designed for an MP-A2 coil configuration using half-bridge and full-bridge inverter topologies to drive the primary coil (LP) and

a series capacitance (CP). Within the operating frequency range from 110kHz to 145kHz, the assembly of the primary coil and shielding has a

self-inductance of LP = 10.0μH ±10%, and the value of the series capacitance on the P9242-R-EVK is CP = 215nF ±5%. Near resonance, the

voltage developed across the CP series capacitance could reach 70V peak. High-voltage (100V) COG-type ceramic capacitors are highly

recommended for their AC and DC characteristics and temperature stability. The recommended parts are listed on the bill of materials (BOM)

in Table 22.