Abstract: A method of tuning the resonance frequency of a transponder to a target frequency is described, wherein a transponder comprises a film antenna with an IC (IC) mounted to the film antenna (L) and an integrated resonance capacitor (C) is part of a IC. During testing of IC at chip probe to determine the pass/fail of the IC, the integrated resonance capacitor (C) is measured and the value is stored with the pass/fail data of the wafer map. Then after mounting a passed IC (IC) to a film antenna (L) with variable inductance, retrieve the integrated resonance capacitance value from the wafer map and calculate the amount of inductance necessary to achieve the target frequency. Tune the film antenna (L) to achieve the necessary inductance, measure the transponder resonance frequency, and compare the transponder resonance frequency to the target frequency.

Abstract: A transponder device (10) includes a discharge circuit (18) to control the discharge of voltage from a charge capacitor (14). The discharge circuit (18) prevents transmission of a data telegram by the transponder device (10) until a voltage of the charge capacitor (14) reaches a threshold voltage level. The threshold voltage level is sufficient to ensure that a complete transmission of the data telegram is performed. Upon reaching the threshold voltage level, a transponder analog and digital circuit (19) initiates transmission of the data telegram. A control logic circuit (32) activates a counter (36) upon the start of the data telegram transmission. The counter (36) generates a control signal that is used to bypass the discharge circuit in order that the charge capacitor (14) can be connected directly to the transponder analog and digital circuit (19).