摘要:
A Digital power amplifier (13) to drive an RFID antenna (10) with a substantial sinusoidal output current (I) which digital power amplifier (13) comprises: an integrated circuit (IC2) with a first transmission output pin (15) and a second transmission output pin (16) to provide an output signal (17); an adaption circuit (14) of discrete components (C2a, C2b) connected to the first and second transmission output pin (15, 16) to adapt the output signal (17) and feed the substantial sinusoidal output current (1) with a transmission resonance frequency to the RFID antenna (10), wherein the integrated circuit (IC2) comprises: a digital control section (19) with a number ofN wave-forming contacts (20) to output a digital wave-forming bit combination of N bits with a clock frequency M-times the transmission resonance frequency; a number ofN driver blocks (21) each connected with a first contact (22) to one of the wave-forming contacts (20) and a number of N/2 of them connected with a second contact to the first transmission output pin (15) and the other number of N/2 of them connected with their second contact to the second transmission output pin (16), which driver blocks (21) are built to provide increments of the substantial sinusoidal output current (I) to the first and second transmission output pin (15, 16).