TIDUF28 November 2023
The digital interface is simple with just a modulator clock input and a bit-stream data output. R28 is a 51-Ω serial termination resistor. The capacitor C42 is optional for slew rate reduction with lower radiated emissions (EMI), if required. The radio frequency (RF) filter R27 and C41 with a cutoff frequency of 95-MHz is optional to attenuate high-frequency RF noise on the clock signal, if present in the system.
A single modulator clock signal MCU_CLK_I needs to be provided by the MCU for the three current sensing modulators. Figure 3-7 shows that the corresponding clock buffer outputs have 51-Ω series termination and are routed in star topology with similar length to each of the three AMC1306M05 modulators. The AMC1306M05 supports modulator clocks from 5 MHz to 21 MHz.