A transponder and method for operating a transponder, which has a capacitor (Cbuf) for storing power transmitted via an air interface and an arithmetic logic unit (10) that can be supplied with the stored power, in which a capacitor voltage (VC) of the capacitor (Cbuf) is compared with a first threshold (V1), in which the capacitor voltage (VC) is compared with a second threshold (V2), whereby the first threshold (V1) and the second threshold (V2) are different, in which in a first operating mode (M1), when the capacitor voltage (VC) is above the first threshold (V1), the arithmetic logic unit (10) performs a number of routines with a different priority, in which in a second operating mode (M2), when the capacitor voltage (VC) is between the first threshold (V1) and the second threshold (V2), a number of low-priority routines are stopped and a number of high-priority routines are continued.