
MNL-0641-01 Rev A3
ECO-4823
Effective: 04 Oct 16
Page 59 of 107
20
LED_ nRESET
21
LED_CLOCK
22
LED_PWR
23
LED_DO
24
LED_GND
These pins implement a serial interface that outputs a string of LED on/off bits that indicate the status of
the Ethernet ports and the overall status of the switch. The schematic in Figure 22 shows the
recommended circuit that the standard firmware can drive to support two LEDs for each of the 20 copper
Ethernet ports on the SWI-22-10-10.
Figure 22. Recommended SWI-22-10-10 LED Port Interface Circuit
The schematic in Figure 23 shows the recommended circuit that the standard firmware can drive to
support two LEDs for each of the 8 copper Ethernet ports on the SWI-22-10-01.
Figure 23. Recommended SWI-22-10-01 LED Port Interface Circuit
If the LED Port Interface Circuit is to be located more than a few inches from the SWI-22-10, it is
recommended that all four of the LED interface signals be driven by Schmitt-trigger input non-inverting
buffers to reduce loading and improve signal quality on those signals.