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Publication No. 980938 Rev. K
Model T940 User Manual
Astronics Test Systems
DR4 Driver/Receiver Board E-3
Signal Descriptions
DATA
Channel data output signals from the Data Sequencer to
the programmable output drivers.
EN
Channel enable output signals from the Data Sequencer to
the programmable output drivers.
OC
Over-Current detect from the programmable Driver and
Receiver channels.
RH/RL
Response High input signals to the Data Sequencer from
the programmable input receivers. 1 = good 1,
0 = good 0.
Response Low input signals to the Data Sequencer from
the programmable input receivers. 0 = good 0, 1 = good 1.
CONTROL
Control Logic signals to control isolation relays,
termination, pin electronics and temperature thresholds.
CHA [1:24]
These are Bi-directional programmable I/O channels from
CHB [33:56]
the DR4 Drivers and Receivers connected to the UUT
TEMPMON
Real-time temperature monitors the PCB junction plane.
SHUTDOWN
These are signals that control the driver output used in
Direct Drive mode.
SEQUENCER A T940 Digital Board Sequencer logic that provides the
Stimulus and captures Response data.
SEQUENCER B T940 Digital Board Sequencer logic that provides the
Stimulus and captures Response data.
+48V
This is the common power bus from used by the Prog
Positive and Prog Negative regulators.
DAC
Provides the reference used to generate the
programmable Positive and Negative Regulator Voltages.
CHANNELS TO MUX/ADC
DC levels of the High Voltage Channels is measured using
these signals for Field Calibration.
PROG POSITIVE/NEGATIVE REGULATORS
These programmable regulators provide the bias power for
the High Voltage channels. There are three GROUP power
regulators.
CHANNELS TO MUX/ADC
DC levels of the High Voltage Channels is measured using
these signals for Field Calibration. The ADC can also be
used to monitor other board voltages including the Power
Regulators.