| 摘要 |
A circuit (60) for converting a digital value into an analogue signal is described. The circuit comprises a logic block (64) arranged to receive one or more digital signals representing the value and each having a relative weighting. The logic block is further arranged to output one or more signals, each output signal comprising an oscillator signal modulated by a respective digital signal. The circuit (60) further comprises generating means (69) for generating an analogue signal representative of the digital value. The analogue signal comprises a weighted combination of the signals output from the logic block (64), the relative weightings being based on the relative weightings of the respective digital signals. The logic block (64) may comprise a series of multiplying elements (61 a-c), such as logic gates or series switches, each multiplying element arranged to receive an oscillator signal as a first input and a respective digital signal as a second input, and arranged to multiply the oscillator signal with the digital signal. The generating means (69) may comprise a series of amplitude modifiers (62a-c), such as a capacitor, a resistor and an inductor, arranged to modify the relative amplitudes of the signals output from the logic block (64). The generating means (69) may comprise means (66) to sum the amplitude-modified signals |
