1Pps Output - Safran VersaSync User Manual

1.7 VersaSync Specifications
Oscillator Type
mRO-50
Table 1-10:
Oscillator
Type
OCXO
mRO-50
Table 1-11:
Oscillator Type
For more information, see
1.7.3.2

1PPS Output

Signal: One pulse-per-second square wave (ext. reference connected to GNSS
receiver)
Signal level: TTL compatible, 4.3 V minimum, base-to-peak into 50 Ω
Pulse width: Configurable pulse width (200 ms by default)
Pulse width range: 20 ns to 900 ms
Rise time: <10 ns
Accuracy: Positive edge within ±50 ns of UTC when locked to a valid 1PPS input
reference
Table 1-12:
Oscillator
Type
OCXO
mRO-50
20
-12
1x10
5x10
10 MHz output — oscillator stability
Short-Term Stability (Allan variance)
1 sec. 10 sec.
-9
1x10 1x10
-11
4 x 10 1.3 x 10
10 MHz output — oscillator phase noise (dBc/Hz)
@ 10 Hz
OCXO ˗120 dBc/Hz
mRO-50 ˗90 dBc/Hz
1PPS output accuracies
1PPS Accuracy to UTC
(1 sigma, locked to
GPS)
±50 ns
±50 ns
typical 24-hour average locked to GPS
-12
per day typical aging unlocked
100 sec.
-10 -11
3x10
-11 -12
4 x 10
@ 100 Hz
˗140 dBc/Hz
˗110 dBc/Hz
"Configuring the Oscillator" on
Holdover (constant temp. after 2 weeks of GPS
After 4 hours
3 μs
0.2 μs
CHAPTER
Accuracy
Relative Frequency Variation
with Temperature (0°C to
60°C)
±5x10
4x10
@ 1KHz
˗150 dBc/Hz
˗135 dBc/Hz
page 223.
lock)
After 24 hours
40 μs
1.5 μs
•
1 VersaSync User Manual Rev. 12
-8
-10
@ 100 KHz
˗155 dBc/Hz
./.
After 7 days
1.2 ms
20 μs