Summit drives support capacitive coupling as an alternative to magnetic coupling for EtherCAT communication over short distances. This feature is particularly advantageous when daisy-chaining multiple drives on the same PCB, offering several benefits at the expense of slightly higher power consumption (around 10 mA per axis):
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Cost reduction (huge difference compared to magnetics)
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Simplified design
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Smaller footprint
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Reduced complexity
To enable capacitive coupling, a 1 kΩ pull-down resistor must be connected to the \ETHx_LED_LINK pin of each port where capacitive coupling is desired. If it is necessary to drive an LED, use an inverting buffer to drive the LED anode or an open-collector device to sink the cathode current.
The figure below shows the intended implementation of the connection between Port 1 of the first drive and Port 0 of the second drive using a 100 nF, 0402, X7R ceramic capacitor. Ensure that the TX pair of one port is connected to the RX pair of the other port, while always maintaining the correct polarity of the positive and negative lines:
