Number of Channels48
Input Voltage Range0 to 50 volts
Input Impedance> 1 M Ohm
Selectable Pull-Up10 k Ohm per channel,
controlled for each group of 16
connected to an external pull-up voltage source
Selectable Pull-Down10 k Ohm per channel,
controlled for each group of 16
connected to ground
Comparator Window / Threshold Sources4, programmable, 0 to 50 V range
Resolution: 12 mV
Accuracy: ±100 mV + 2% of programmed value
Window ComparatorChannels 1 – 16,
programmable high and low thresholds
Threshold ComparatorChannels 17 – 48,
programmable threshold voltage sources
for channels 17-32 & channels 33-48
Comparator Response Time400 ns (typ), 1 us max.
Comparator Channel Voltage MeasurementRange: 0 to 50 V
Resolution: 12 mv
Accuracy: ±5 mV



SourceAny or all of the 48 comparator channels
Event Hold-off TimeResolution: 1 us
Range: 1 uSec to 1 Second
FunctionalityTimestamp events and / or states from any of the (3) comparator channels
Number of Channels3
Source3 of the 48 comparator channels
Recorded Events or States12K max.
Timestamp Resolution1 usec (min)
Timestamp Range1 uSec to 1 mSec
Selectable 1 x 2N, N = 0 to 15 uSec
Timestamp Record Duration4 min. @ 1 usec resolution



FunctionalitySamples input of one selected channel from each group
Number of Channels3
Source(1) from each group
Sample Memory83,700 Samples per channel (max.)
Sample Clock Resolution1 uSec
Sample Clock Range1 uSec to 1 mSec
Selectable 1 x 2N, N = 0 to 8 uSec




PXI Bus10 MHz
Internal80 MHz oscillator, ±20 ppm



FPGA TypeAltera Stratix III, EP3SL50F780
Number of PLLsFour
Logic Elements47.5 K
Internal Memory1.836 Mb
On-Board Memory256 K x 32 SSRAM
On-Board Flash16 MB



Digital I/O Inputs3 bits
Logic LevelTTL



3.3 VDC1.5 A max.
5 VDC0.4 A typical, 1 A max.
+12 VDC0.5 A max.
-12 VDC0.1 A max.



Operating Temperature RangeGX3748: 0 °C to +50 °C
GX3748-M: 0 °C to +83 °C; contact factory for extended temperature range specifications
Storage Temperature Range-20 °C to +85°C
Relative Humidity (operating)5% to 85%, temperature range 0°C to 60°C
5% to 60% for operating temperatures above 60°C
Altitude (operating)4600 meters (max)
Connector62 pin, D-sub female
Size3U PXI, hybrid slot compatible
Weight200 g