A flame amplifier for flame monitoring in a burner, with an ionization voltage generator for generating an AC voltage as an ionization voltage, an ionization electrode for applying the ionization voltage to a flame generated by the burner, so that the flame, acting as a rectifier, generates a DC voltage from the ionization voltage as a flame voltage, and a DC current flows as a flame current, and with flame signal processing with a low-pass filter to the input side of which a mixed voltage formed by ionization voltage and flame voltage as well as a mixed current with an AC component and a DC component corresponding to the flame current are applied, wherein the ionization voltage generator is configured to generate the ionization voltage with a frequency of more than 60 Hz, and wherein the low-pass filter has a cut-off frequency corresponding to the frequency of the ionization voltage, so that the AC component of the mixed current is blocked and the low-pass filter has a time constant corresponding to the frequency of the ionization voltage, so that, from an unfiltered flame signal applied to the input side of the low-pass filter, a flame signal (6, 8) filtered on the output side and corresponding to the flame current is generated, wherein the flame amplifier has evaluation electronics which is signally connected to an output of the low-pass filter and is configured to evaluate the flame signal (6, 8) corresponding to the flame current and to determine a state of the flame, characterized in that the evaluation electronics is configured to compare values of the filtered flame signal (6, 8) and/or mean values formed by the evaluation electronics from the flame signal (6, 8) to a switch-off threshold, wherein, with a value less than the switch-off threshold and/or if falling below the switch-off threshold, a delay time (τ) is waited and an extinguished flame is only detected as the state of the flame if subsequent values within the delay time (τ) are less than the switch-off threshold. wherein the ionization voltage generator is configured to generate the ionization voltage with a frequency of more than 60 Hz, and wherein the low-pass filter has a cut-off frequency corresponding to the frequency of the ionization voltage, so that the AC component of the mixed current is blocked and the low-pass filter has a time constant corresponding to the frequency of the ionization voltage, so that, from an unfiltered flame signal applied to the input side of the low-pass filter, a flame signal (6, 8) filtered on the output side and corresponding to the flame current is generated, wherein the flame amplifier has evaluation electronics which is signally connected to an output of the low-pass filter and is configured to evaluate the flame signal (6, 8) corresponding to the flame current and to determine a state of the flame, characterized in that the evaluation electronics is configured to compare values of the filtered flame signal (6, 8) and/or mean values formed by the evaluation electronics from the flame signal (6, 8) to a switch-off threshold, wherein, with a value less than the switch-off threshold and/or if falling below the switch-off threshold, a delay time (τ) is waited and an extinguished flame is only detected as the state of the flame if subsequent values within the delay time (τ) are less than the switch-off threshold.