method for nonlinear transformation of a pulsamplitudenmodulierten input signal in a pulskodemoduliertes signal by means of a zaehlkodierers

摘要

The PAM/PCM nonlinear code converter uses a counter. The PAM input signal is passed via a switch to the first input of a differential amplifier. This amplifier is sensitive only over a very narrow voltage range and the switch is closed only during sampling. The differential amplifier's output polarity is stored during the switch's closed time. When the switch opens the coding capacitor is discharged and the polarity of the resulting output voltage is compared with the stored polarity to determine the end of counting.