Time quantization derivative PWM based one-bit DPCM

A new 1-bit DPCM (differential pulse code modulator) circuit based on the derivative PWM (pulse width modulation) signal is proposed. The main concept of the proposed technique is that the difference of the adjacent input sample resides in the duty cycle of the derivative PWM signal. Therefore, one-bit digital signal can be exploited from the derivative PWM waveform in which the quantization process is performed in time axis, not in conventional amplitude axis. The derivative PWM principled circuit, which is composed of 3 OTAs, 1 capacitor, and 2 resistors, provides the simplicity and compactness of the circuit´s structure. In addition, the sampling operation is inherent in the derivative PWM circuit thus only some additional components are required for the mentioned transformation process. Implicitly, the proposed circuit is suitable for integrated circuit fabricating technology. The PSPICE simulation outputs of the proposed technique have demonstrated the expected results. Also, SNR analysis of the quantization process is briefly discussed.