Echelon LonWorks Router User Manual

Page 101

inches) along a clean surface. Dirty surfaces can allow arcing over even longer

creepage distances.
When ESD hits to circuitry cannot be avoided through creepage, clearance, and

ground guarding techniques (that is, at external connector pins), explicit

clamping of the exposed lines is required to shunt the ESD current. In general,

exposed lines require diode clamps to the power supply rails or Zener clamps to

chassis ground to shunt the ESD current to ground while clamping the voltage

low enough to prevent circuit damage. The Neuron Chip’s communications port

lines are connected directly to the RTR-10 edge connector without any ESD

protection beyond that provided by the chip itself. For a Series 5000 router

device, consider how the communications port lines are connected to other parts

of the router device. If these lines will be exposed to ESD in a custom router,

protection must be added to the router motherboard.

ORKS

Router User’s Guide