Teledyne LeCroy PC_AT 200 - Manual (Page 3)

1
INTRODUCTION
These Active Extenders allow insertion or removal of the UUT into any PC/AT
bus without having to turn the system Off and On. This feature eliminates
repeated system power cycling and rebooting. Therefore speeds up rework,
characterization and test of UUT in the development phase as well as production
testing. The elimination of the repeated power cycling also helps prolonging
the system life and the hard disc operation. These Active Extenders use a new
CMOS technology for switching the signals on and off. These switches have a
very fast propagation delay, typically about 250 picoseconds, resulting in no
timing degradation between the bus and the UUT. The switches are also
bidirectional allowing the entire address range to be supported without any
jumper setting or running a background software to use the board.
These Active Extender boards isolate all signals and voltages to the UUT
when the On-Off switch is in the Off position. All voltages are ramped down
and ramped up during the power down and power up to eliminate any spikes.
During the power down the signals to the bus become isolated as soon as the
main supply, +5V, reaches down to +3.7V and during the power up the signals
stay isolated until the main voltage is at least +3.7V.
These Active Extenders also allow voltage margin testing of the UUT by
allowing external power supplies to replace the bus supplies as the inputs to
the UUT.
An on-board current-to-voltage converter for the main supply, +5V, allows
current measurement of the +5V at any time, using just a voltmeter at the J5
test points. The maximum current draw for the +5V supply is set to 5 Amp at
the
factory.
INSTALLATION
To install the Active Extender, make sure to turn the PC power off. Insert
the Active Extender in any available slot and secure it's bracket to the main
chassis. You are now ready to use your new extender board.
NOTE: If you are planning to use software to control the board, the On-Off
switch must be in the Off position and the dip switches must be in the OPEN
position, otherwise, all of the switches on the dip switch must be in the
CLOSED
position.
NOTE: The software command is disabled at the factory by not having the
JP16 installed. To enable the software command operation please install JP16.