SBASA56 September 2023 AMC131M02
PRODUCTION DATA
The AMC131M02 uses an on-off keying (OOK) modulation scheme to transmit the modulator output bitstream across the capacitive SiO2-based isolation barrier. After transmission across the isolation barrier, the modulator output bitstream is decimated using the sinc filter to reconstruct the ADC conversion data, and is then transferred to the digital control so that the data are accessible through the SPI interface. Figure 8-1 depicts the block diagram of an isolation channel. The transmitter modulates the bitstream at TX IN with an internally generated, 480-MHz carrier and sends a burst across the isolation barrier to represent a digital one and sends a no signal to represent the digital zero. The receiver demodulates the signal after advanced signal conditioning and produces the output. The symmetrical design of each isolation channel improves the common-mode transient immunity (CMTI) performance and reduces the radiated emissions caused by the high-frequency carrier.
Figure 8-2 shows the concept of the on-off keying scheme.