EWA CORELIS PXIE-1149.1/4E, Руководство пользователя, Страница: 20 / 41

Using the PXIE-1149.1/4E with ScanExpress
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The following PXIE-1149.1/4E TAP connectors are connected to the target board:
TAP1 - when the target has a single TAP connector
TAP1 and TAP2 - when the target has 2 TAP interface connectors
TAP1 , TAP2 and TAP3 - when the target has 3 TAP interface connectors
TAP1 , TAP2 , TAP3 and TAP4 - when the target has 4 TAP interface connectors
To connect the TAP cables to the target (UUT), follow these steps in the order as follows:
1. Verify that the target power is OFF.
2. Plug the TAP cable connector to the mating target header.
3. Now you can turn the target power ON.
ALERT !
Make sure your target board is connected to GROUND prior to powering up the target
board. This assures that the target-power return flows through its power supply return
(GND) signal and not through the ground wire of the PXIE . Otherwise, with a ‘floating’
target, if the user hot-plugs the tar get power cable from its external supply (such as a ‘brick’ type
power supply), there is no guarantee that the ground will make contact with the target first,
before the power does. In such case, it is possible to momentarily engage the voltage pin of the
target power supply connector prior to engaging the ground (return) pin. During such action, all
target current will momentarily flow through the PXIE to ground, with the resulting transients
possibly resetting the PXIE-1149.1/4E unit.