Pin
Description
Color
Indication
Green
The device is receiving data.
Table 9. LED Descriptions The LED indications described in the following table occur only when
you use the NI-USRP API with the default FPGA image. When you use LabVIEW FPGA, you
customize the LED indications.
Back Panel
0
1
PWR
REF
IN
PPS
OUT
TRIG
5V DC
REF
OUT
1G/10G ETH
3.3 V
+15 dBm
MAX
9-16V DC
7.5 A MAX
SFP+Ports
PCIe x4
TRIG
3.3V
IN
5V MAX
PPS
GPS
ANT
–15 dBm
MAX
Connector
Description
PWR
Input that accepts a 9 V to 16 V, 6 A external DC power connector.
1G/10G ETH Ethernet port that accepts 1G SFP modules and 10G SFP+ modules. With a 1G ETH
module inserted, the ports accept gigabit Ethernet-compatible cables (Category 5,
Category 5e, or Category 6).
REF OUT
Output terminal for an external reference signal for the LO on the device. REF OUT
is a female SMA connector with an impedance of 50 Ω, and it is a single-ended
reference output. The output signal at this connector is 10 MHz at 3.3 V.
REF IN
Input terminal for an external reference signal for the LO on the device. REF IN is a
female SMA connector with an impedance of 50 Ω, and it is a single-ended
reference input. REF IN accepts a 10 MHz signal with a minimum input power of 0
dBm (0.632 V
pk-pk
) and a maximum input power of 15 dBm (3.56 V
pk-pk
) for a
square wave or sine wave.
PCIe x4
Port for a PCI Express Generation 1, x4 bus connection through an MXI Express
four-lane cable.
PPS TRIG
OUT
Output terminal for the pulse per second (PPS) timing reference. PPS TRIG OUT is
a female SMA connector with an impedance of 50 Ω, and it is a single-ended input.
The output signal is 0 V to 3.3 V TTL. You can also use this port as triggered output
(TRIG OUT) that you program with the PPS Trig Out I/O signal.
PPS TRIG IN Input terminal for pulse per second (PPS) timing reference. PPS TRIG IN is a female
SMA connector with an impedance of 50 Ω, and it is a single-ended input channel.
PPS TRIG IN accepts 0 V to 3.3 V TTL and 0 V to 5 V TTL signals. You can also use this
port as a triggered input (TRIG IN) that you control using NI-USRP software.
ni.com
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USRP-2940/2942/2943/2944/2945 Getting Started
