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Model T940 User Manual
Publication No. 980938 Rev. K
DR9 Driver/Receiver Board H-6
Astronics Test Systems
1 = good 1.
V+/V-
Bias Power required for operation of the Pin Electronics
devices.
EXTSENSE
Pin electronics signal used for calibration.
DUT_GND
This signal comes from the UUT and can be used to offset
the reference levels up to ±3V. Excursions of DUT_GND
beyond ±390 mV with respect to signal ground yield a
GND FAULT signal.
I/O CONTROL
Control Logic signals to control isolation relays,
termination, pin electronics and temperature thresholds.
CH 1-24
UUT Bi-directional programmable I/O channels from the
DR9 Drivers and Receivers
ACH 1-24
These provide a means to connect to the DR9 DIGITAL
CHANNELS to ANALOG TEST resources. The DIGITAL
CHANNEL isolation relay is opened before the ANALOG
CHANNEL relay is closed to avoid damage to the Pin
Electronics (Break-Before-Make).
MONITOR
This is an analog output signal from the Pin Electronics
devices which can be used to monitor DAC levels even the
Channel I/O levels. This signal is used with the internal
ADC but a buffered version also comes out the Front
Panel.
GND_REF
This is the ground reference output signal from the Pin
Electronics devices. It is used with MONITOR to make
accurate ADC measurements. A buffered version also
comes out the Front Panel.
EXTFORCE
External Force is an analog I/O signal which is connected
to all of the Pin Electronics devices and can be used to
force a level on the output of the driver. It may also be
used to monitor a channel’s state. EXTFORCE is also
used for calibration.
OVERVOLT
Real-time over-voltage detector circuit monitors Driver and
Receivers to protect the pin electronics. Also clamps the
inputs to the V± rails.
TEMPMON
Real-time temperature monitors for the pin electronics.
Control Logic
The control logic contains the registers, memory and logic that allow the
digital board to interface and configure the hardware. See Figure H-5.