CDA-2990 Specifications

These specifications apply to the CDA-2990 Clock Distribution Device and the CDA-2990 Clock Distribution Device with GPSDO. When not otherwise specified, the specifications for the CDA-2990 in this document refer to both the CDA-2990 and the CDA-2990 with GPSDO.

Note For more detailed specifications of the CDA-2990, refer to the OctoClock CDA-2990 KnowledgeBase.

Definitions

Warranted specifications describe the performance of a model under stated operating conditions and are covered by the model warranty.

Characteristics describe values that are relevant to the use of the model under stated operating conditions but are not covered by the model warranty.

  • Typical specifications describe the performance met by a majority of models.
  • Nominal specifications describe an attribute that is based on design, conformance testing, or supplemental testing.

Specifications are Characteristics unless otherwise noted.

Conditions

Specifications are valid at 25 °C unless otherwise noted.

Hardware Front Panel

Figure 1. Clock Distribution Accessory Front Panel


Input

Table 1. Reference Clock Input
Frequency 10 MHz
Power range 0 dBm to 20 dBm (0.632 Vpk-pk to 6.325 Vpk-pk into 50 Ω)
Coupling AC
Impedance 50 Ω
Table 2. PPS Input
Voltage, recommended minimum 2.5 V
Voltage, recommended maximum 5 V
Voltage, operating maximum 5.3 V
Voltage, absolute maximum 6.8 V
Voltage, maximum logic level low (VIL) 0.74 V
Voltage, minimum logic level high (VIH) 1.8 V
Compatible logic families TTL, CMOS, LVTTL, LVCMOS

Output

Note In addition to the ability to distribute external sources, the CDA-2990 with GPSDO can also generate clock and PPS signals internally. To activate the GPSDO, move the switch on the front panel to INTERNAL.
Table 3. Clock Output
Frequency 10 MHz
Frequency accuracy without GPSDO Dependent on input
Frequency accuracy with GPSDO, unlocked 25 ppb
Power 10 dBm, typical
Voltage 1.4 Vpk-pk
Waveform Square wave
Impedance 50‎ Ω
Coupling AC
Table 4. PPS Output
Voltage, maximum 5 V
Positive duty cycle 20%, typical
Period 1 s, typical
Waveform Logic-level pulse
Table 5. Accuracy
Without GPSDO Dependent on input
With GPSDO, unlocked <±20 µs
With GPSDO, locked 50 ns
Note Accuracy wwith GPSDO, unlocked is measured over a 3-hour period at 25 °C (OCXO, no motion).

GPS Disciplined Oscillator (GPSDO)

Table 6. Active antenna
Voltage 5 V
Power 0.7 W
GPS Frequency L1, C/A 1,574 MHz
GPS Antenna Active or passive
Table 7. Sensitivity
Acquisition -142 dBm
Tracking -158 dBm
Table 8. GPS TTFF
Cold start <45 s
Warm start 1 s
Hot start 1 s
Allan deviation (ADEV) 1 × 10-12
Warm-up/stabilization time (To 1 × 10-8 accuracy) <5 min
Note Allan deviation measured at 10 ks (OCXO, GPS locked, no motion).
Note NI recommends periodically locking the GPS for at least 1 hour to recalibrate the GPSDO module accuracy.

Power Supply

Table 9. Power Supply
Input voltage 6 V to 15 V DC
Input power 6 W maximum

Physical Characteristics

Table 10. Physical Characteristics
Dimensions (L × W × H) 4 in. × 17.19 in. × 1.75 in. (10.16 cm × 43.66 cm × 4.45 cm)
Weight 2.6 lb (1.18 kg)
Note For detailed information about connectors and key components, refer to the OctoClock CDA-2990 KnowledgeBase.

Environment

Table 11. Environmental Characteristics
Operating temperature 23 °C ± 5 °C, room temperature.
Operating relative humidity range 10% to 90%, noncondensing (tested in accordance with IEC 60068-2-56)
Maximum altitude 2,000 m (800 mbar) (at 25 °C ambient temperature)
Pollution Degree 2

Indoor use only.