Target System Is Externally Powered - Equinox Systems ISPnano I Series User Manual

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Datasheet of ISPNANO S3 KIT - ISP PORTABLE PROGRAMMER
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4.5 Target System is externally powered

If the Target System (UUT) is powered from an external power supply or via the ICT / ATE i.e. not
from the programmer, then special care should be observed to prevent arcing of the contacts on the
TVCC relay. As the external power supply will be switched through the 'TVCC' pin, through a relay to
either the programmer or ATE / ICT system, there may be a significant current flowing when the relay
is switched on. This could cause arcing of the contacts which will reduce the lifetime of the relay.
To prevent relay contact arcing....
When switching the relays ON or OFF, it is recommended that the external power supply
•
which is powering the Target System (UUT) is switched OFF.
If the external power supply originates from the ATE / ICT, then instruct the ATE / ICT to
•
switch off the power supply.
If the external power supply originates from the Target System side, use a separate relay or
•
electronic switch to switch off the power supply.
114 ISPnano Series Programmer - User Manual – V1.11 – 12
th
May 2011