A measurement method for estimating junction temperatures of a power semi-conductor module comprising: a. duplicating a pulse current in two duplicated pulse currents; b. injecting simultaneously - a first duplicated pulse current to a control electrode of a power transistor of said power semi-conductor module, and - a second duplicated pulse current to an emulator circuit comprising a resistance (R emu) in series with a capacitor (C emu); c. comparing a voltage signal (V ge) across said control electrode of said power transistor and a voltage signal (V emu) across said emulator circuit in such a way to generate a comparison signal (V CMP); characterized by: d. in function of said comparison signal (V CMP), measuring duration (Δt) of said voltage signal (V ge) of said power transistor to reach the same value as said voltage signal (V emu) of said emulator circuit; e. converting said measured duration (Δt) into an estimated value of a junction temperature (T J); f. modify the value of said resistance (R emu) across the emulator circuit such that a corresponding temperature estimation range is modified and that the estimated value of a junction temperature (T J) get closer to the middle of the modified temperature estimation range; g1. if the estimated value of the junction temperature (T J) is sufficiently centered in the middle of the modified temperature estimation range according to predefined criteria, modify the value of said capacitor (C emu) of the emulator circuit such that the sensitivity is increased; g2. if the estimated value of the junction temperature (T J) is not sufficiently centered in the middle of the modified temperature estimation range according to said predefined criteria, modify the value of said capacitor (C emu) of the emulator circuit such that the sensitivity is decreased. a. duplicating a pulse current in two duplicated pulse currents; b. injecting simultaneously - a first duplicated pulse current to a control electrode of a power transistor of said power semi-conductor module, and - a second duplicated pulse current to an emulator circuit comprising a resistance (R emu) in series with a capacitor (C emu); - a first duplicated pulse current to a control electrode of a power transistor of said power semi-conductor module, and - a second duplicated pulse current to an emulator circuit comprising a resistance (R emu) in series with a capacitor (C emu); c. comparing a voltage signal (V ge) across said control electrode of said power transistor and a voltage signal (V emu) across said emulator circuit in such a way to generate a comparison signal (V CMP); characterized by: d. in function of said comparison signal (V CMP), measuring duration (Δt) of said voltage signal (V ge) of said power transistor to reach the same value as said voltage signal (V emu) of said emulator circuit; e. converting said measured duration (Δt) into an estimated value of a junction temperature (T J); f. modify the value of said resistance (R emu) across the emulator circuit such that a corresponding temperature estimation range is modified and that the estimated value of a junction temperature (T J) get closer to the middle of the modified temperature estimation range; g1. if the estimated value of the junction temperature (T J) is sufficiently centered in the middle of the modified temperature estimation range according to predefined criteria, modify the value of said capacitor (C emu) of the emulator circuit such that the sensitivity is increased; g2. if the estimated value of the junction temperature (T J) is not sufficiently centered in the middle of the modified temperature estimation range according to said predefined criteria, modify the value of said capacitor (C emu) of the emulator circuit such that the sensitivity is decreased. g1. if the estimated value of the junction temperature (T J) is sufficiently centered in the middle of the modified temperature estimation range according to predefined criteria, modify the value of said capacitor (C emu) of the emulator circuit such that the sensitivity is increased; g2. if the estimated value of the junction temperature (T J) is not sufficiently centered in the middle of the modified temperature estimation range according to said predefined criteria, modify the value of said capacitor (C emu) of the emulator circuit such that the sensitivity is decreased.