摘要 |
An amplifier (1) includes an analogue-to-digital converter (ADC) (7) and a switched capacitor output stage (8). The ADC (7) converts an analogue signal into a digital signal containing a sequence of symbols. The switched capacitor output stage (8) charges and discharges a capacitor to produce charge pulses at an output (3). During discharge, switches selectively couple the capacitor to the output (3) in opposite directions to produce charge pulses of opposing polarity. The values of the symbols in the digital signal are used to decide the polarity of charge pulses. In this manner, amplification can be achieved without introducing a direct current (DC) component to the signal at the output (3). |